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Some Awesome Aussie GPX 6000 Finds

Some Awesome Aussie GPX 6000 Finds

* Some Awesome Aussie GPX 6000 Finds *

The Minelab GPX 6000 Pulse-Induction detector has now been available in Australia for about 3 years. In that time some awesome nuggets have been unearthed throughout Australia. Some of these significant finds have been publicised, and not surprisingly, many fantastic finds have not been publicised for various reasons.

Several big chunks of gold have been recently found in Western Australia.

 

Below are some of the Minelab GPX 6000 finds that have been shared online:

The big nugget shown in the two photos above reportedly weighs  about 13 Ounces  (about 0.4 kg).  My "guesstimation" is that the total weight of all of the above nuggets would be  at least 30 Ounces !

 

 

The nugget shown in the above two photos was detected using the GPX11" coil at a depth of about 1.5 feet.

 

Below are some more finds using the GPX 6000:

“Here are two of the nicest bits for the season, biggest is 5.5 oz (171.2g) and the other is just over an ounce (35.5g). Both found with a 6000 while pushing. Interestingly the big bit was laying flat, in a crevice in a rock bar, about 60 cm down I suppose (from the bottom of the push) but it was not an inverted signal, and I have no idea why.

Every other solid bit I've got from a gram or so up has been an inverted signal. It started off as a normal up down signal, sounded very OK like a few gram specie 10 inches or so down, good but not outstanding. It just got louder and louder the deeper I got. By about 40-50 cm down I knew it was going to be a better bit, maybe an ounce or two even, and I was convinced that it had to be a specie as the signal wasn't inverted.

The pinpointer was going crazy over a red rock stuck in the crack and I couldn't see any gold yet so I was convinced it was under the rock, got the biggest shock when I got that rock out and felt the weight. It was flat and heavy and clearly a nugget but even after giving it a wash I still couldn't see any gold.

Took a couple of days in alibright for the red coating to dissolve. It has about 6 g of rock in it based on an SG test so it's technically a specie but I'm happy to call it a nugget. The smaller bit was in a different spot, in old wash, probably 70 cm or so down from the surface. I had pushed it though so I only had to dig a few inches. Before I dug it I tried detecting it from the surface level and got no response. Had to be down another 6 inches or so before any signal but it was inverted all the way. The bit was in a small crack but standing upright on it's side and it looked bright and shiny like it does now when it was still stuck in the hole.”

 

 

 

An old Aussie gold prospector (who has used all of Minelab’s other pulse-induction detectors over the past decade (e.g. SDC 2300, GPX 5000 & GPZ 7000) has also used the GPX 6000 in Western Australia for 118 days (about 1,000hrs of swinging) and on 100 of those days, his GPX 6000 detected 854 gold nuggets in highly mineralised ground. He mostly used the large Minelab GPX17x13” elliptical Mono coil for excellent ground coverage (“patch hunting”) and depth capability. In fact, the GPX17 coil easily detected two spherical-shaped nuggets (a 5-grammer, and a 6 grammer) at depths of between 40cm and 45cm in highly mineralised ground north of Kalgoorlie. The GPX17 coil also picks up the small bits too – using the proven “Low & Slow” technique. He also found the GPX14 DD coil excellent for use in salty/conductive ground (where it was almost impossible to run a Mono coil), as well as in areas within/nearby high electromagnetic interference (EMI).

 

 

Liz Pickthall spends her spare time detecting in the central goldfields of Victoria.

"I finally had seen and heard enough, and at the age of 28 I decided to go out and invest in my first detector. Only then did I realise my true love for it, and I’ve been addicted ever since. As the years went by and my love for detecting grew, I started to work less and detect more.

After upgrading my metal detector to the GPX 6000, I was keen to upgrade my coil as well. I waited for the release of all brands of coils, and was lucky enough to be able to try before I bought two different coils – one of which was the Coiltek 9” GOLDHAWK.

It didn’t take me long to see that it was the standout performer in all areas including weight and sensitivity – and it worked wonders on all ground types in the Victorian goldfields. I was so impressed by how quiet it ran for such a sensitive coil. The 9” coil has found gold in the most ‘flogged out’ areas, with the coil’s size making it so easy to get in tight areas under and around bushes and trees.”

 

 

 

 

  

 

  

 

 

 

 

 

Imagine how many tens-of-thousands of gold nuggets (& specimens) have been found throughout Australia over only the past 3 years using the mighty Minelab GPX 6000 detector.

Imagine how many more huge chunks of gold are still out there throughout Australia - that have never had a GPX 6000 scan over them !

To boot ..... there are now  SEVEN  (7)  different coils available for the GPX 6000.  Even better - four of these new coils are AUSSIE-MADE.

Coupled with a super-low 1.225 kHz operating frequency of the GPX 6000 - it's no wonder the GPX 6000 is a gold magnet !     (By comparison the GPX 5000 "is configured to operate at a fundamental operating frequency of 5 kHz", and the GPZ 7000 "is configured to operate at a fundamental operating frequency of 3.675 kHz”, whereas for the SDC 2300 "the transmit frequency is about 3 kHz")

With the gold price at an all-time-ever record high (of over AU$3,700 per Ounce in late April 2024) - you only need to find about 2.5 ounces of gold to cover your investment cost of a new GPX 6000.

 

WHERE can I go detecting gold in Queensland ?

WHERE  can  I  go  detecting  gold  in  Queensland ?

 

WHERE  CAN  I  GO  DETECTING  GOLD  IN  QUEENSLAND  ?

Now that’s a great question ! …. that we often get asked by customers/visitors to our store.

To lawfully go detecting gold nuggets (and gold specimens) in Queensland you requireQueensland ‘Fossicking Licence’.

Unfortunately, 'Miners Rights' issued in other States (like W.A. and Victoria) do not apply in Queensland.

You can purchase your Qld Fossicking Licence online using a credit card payment. Costs vary from about $10 for 1 month, up to about $60 for 1 year for an individual fossicker (A one-year Fossicking Licence for a family costs about $80). Your licence is e-mailed to you once payment is confirmed.

Fossicking Laws/Responsibilities

The Queensland Fossicking Act 1994 and it’s associated Regulations contain requirements for fossickers to maintain safety, hygiene and a high standard of behaviour. Infringement notices (on-the-spot fines) and prosecutions may be used to enforce the provisions of the legislation. Breaches may also result in cancellation of licences.

When fossicking in Queensland, some of the general responsibilities include that a person MUST NOT:
•    destroy or injure any trees
•    clear any vegetation except above an actual excavation
•    pollute any watercourse, dam or the like
•    create areas likely to erode
•    interfere with any livestock, wildlife or property infrastructure (e.g. windmills, bores, pumps, tanks, fences)
•    interfere with any heritage or cultural site
•    undermine any banks or dig pits to create any tunnels or overhanging sections.

There are also other requirements a person must follow when fossicking near watercourses, and also upon designated fossicking lands and areas.

When fossicking upon private property in Queensland, a person should also have written permission from the land owner/s.

A Qld Fossicking Licence allows you to search for, and collect fossicking materials using hand tools and for recreational, tourist and educational purposes only.
“Hand tools such as picks, shovels, hammers, sieves, shakers, electronic detectors (metal detectors) and other similar tools can be used.

No machinery is permitted. This includes water sluices with electronic pumps and dredges of any kind.

You can collect from the surface or by digging, but you are not permitted to dig below 2m of the natural ground surface of land or below 0.5m in streams. Overhangs and tunnels are not allowed.”

Also - “You can collect gemstones, ornamental stones, mineral specimens, alluvial gold (including nuggets) and some fossil specimens, but not meteorites and fossils of vertebrate animals. (The finding/ownership of meteorites in Australia will be considered in a future BLOG article).

You don’t need a fossicking licence to search for ‘treasure’ such as lost jewellery and coins on a beach.”

In other words – you can go detecting on public beaches in Queensland in search of coins and jewellery (including those made from gold or platinum or silver) without holding a Qld Fossicking Licence.

However, if you find any item of value, including jewellery – that does not belong to you - then you are required by law to hand such property in to the police. Accordingly, you are entitled to receive an official receipt from the police for the found property you hand in to them. If the police can not locate the lawful owner of that found property within a few months, then you can lawfully lodge a claim to the police for that property you found. Otherwise, if you keep valuable property that you find - that does not belong to you – you may be liable to prosecution for “Stealing by Finding”.

The Qld Police Service website contains  a List of Found Property  (including items of jewellery) reported during the past month. This information may also be useful to someone who has lost an item and not reported it to police.

 

General Permission Areas (GPA's) for Fossicking in Qld
It was recently publicly reported that:  "Queensland currently has 11 fossicking areas, 9 designated fossicking lands, and 21 General Permission Areas (GPA's) for fossicking - totaling more than 20,000 hectares"

There are 11 separate General Permission Areas (GPA's) in the Clermont area where landholders have given general permission for fossicking. Seven of these are in the Clermont State Forest. More than 11,000 Hectares (> 110 square kilometres) of General Permission Areas (GPA's) are available for fossicking near Clermont (about 950km NNW of Brisbane).

A total of about 50 square kilometres of General Permission Areas (GPA's) are available for fossicking at Durikai State Forest, about 30km west of Warwick (about 200km SW of Brisbane).

Also near Warwick (about 30km NW), approximately 5 square kilometres of General Permission Areas (GPA's) are available for fossicking at Talgai State Forest.

We regularly receive feedback (including photos) from customers, and other detectorists/prospectors, about gold nuggets being detected in the above GPA's - mostly found using Minelab Pulse-Induction (PI) technology detectors (e.g. GPZ 7000, GPX 6000, GPX 5000/4500, and SDC 2300).

 

New GPA's Sought

In late 2022 it was reported that "the Rockhampton Regional Council said it had written to the Department of Resources to try to create GPA's in three locations in Mount Morgan."

Like the 'Amalgamated Prospectors & Leaseholders Association' (APLA) of Western Australia, and also the 'Prospectors and Miners Association of Victoria' (PMAV) - perhaps what is required in Queensland is a similar membership-based body created to protect the rights and opportunities of those who wish to fossick and prospect in Queensland. Furthermore, such an Association could lobby the Queensland Government on behalf of it's members to create more opportunities for fossicking & prospecting throughout Queensland, including far more General Permission Areas.

In other States like Western Australia and Victoria there is far more total areas of ground available for fossicking and prospecting with a Miners Right - than there is currently available via GPA's in Queensland.

 

Perhaps the following online information with respect to fossicking areas in Queensland, and Qld Prospecting Permits, may also be of interest to you:

 

Queensland 'Globe'
Queensland Globe is a free online interactive website tool that you can use to identify property names (and their boundaries) including pastoral properties.
e.g. you can select following options:  All Layers > Location > Property Names


Queensland ‘GeoResGlobe’
Queensland ‘GeoResGlobe’ is another free online interactive website tool that you can use to obtain information on Queensland's mining and exploration data, including:
1.    Identify property names (and their boundaries) including pastoral properties; and
2.    Identify ‘Exploration Permits - Minerals’ (EPM’s) – either “Granted” (current) or “Application” (pending assessment); and

3. Identify 'Mining Leases' (ML's) -

covering areas/properties of interest to you. Additional available information includes the “Authorised Holder Name” of the EPM’s / ML's, as well as the “Grant Date” and “Expiry Date’ of them.


 
Upon accessing this interactive website tool, you can use the menu system on the left hand side.
Click on “Layers” > “Add Layers” > “All Layers”
Then you can choose from a list of different Layers, and also the sub-layers within each Layer (e.g. “Cadastre” > “Properties”).

Example 1 of available information - a simple search via the Qld ‘GeoResGlobe’ database revealed that:  in early May 2023 an Application was lodged for a Minerals Exploration Permit (EPM 28787) covering 230 square kilometres to the west & north-west of Durikai State Forest. Interestingly, in April & May 2023 the same Applicant also lodged EPM Applications for other areas within and around Durikai State Forest.

 

Example 2 of available information - a simple search via the Qld ‘GeoResGlobe’ database - using the menu system on the left hand side, by Clicking on “Production permits” > “Mining lease” > “ML granted”, and then selecting the letter "i" Information tool and then clicking this tool within the marked area of ML 1870 on the map, provides further information at the bottom of the screen - which revealed that within the Blair Athol State Forest, Mining Lease ML 1870 (re: "Au" - gold) was granted in 1980 and is current until June 2026, including the name of the leaseholder.



Contacting Exploration Permit Holders/Mining Companies
During my recent several years of full-time prospecting, I contacted several gold exploration and mining companies, and after voluntarily submitting written details (via e-mail) about my prospecting experience, vehicle/s, prospecting techniques & gear (including safety equipment), my Prospecting Licence/Miner's Right, and public liability insurance etc., and my intentions – I was very fortunate to be granted written conditional permission to prospect on their leases. As a result, I provided details (photos & GPS co-ordinates) of all my finds of gold nuggets to the leaseholders, who then permitted me to explore additional ground held via their leases.


Properties Allowing Prospecting & Camping
There are several properties (including large stations) throughout Queensland that permit recreational prospecting/camping for a fee. These include locations near: Georgetown/Forsythe in North Qld, and Warwick ('Glendon Camping Ground' – which is beside Durikai State Forest) in South-East Qld, and Clermont & Mount Morgan in Central Qld, and Palmerville Station in Cape York Peninsula, etc

https://www.facebook.com/flatcreekstation/

https://www.facebook.com/people/Western-Creek-Gold/100066532061530/

https://www.gilbertongold.com/

https://glendoncamping.com.au/

https://www.facebook.com/people/Fig-Tree-Camp/100066735554908/

https://goldenprospectingtours.com.au

https://mountmorganoutdoors.com.au/product/car-lyn-fossicking-off-grid-camping-property-mount-morgan/

https://www.facebook.com/people/Palmerville-Gold/100065218831323/ 

 

The website 'Hipcamp' also features several properties that permit camping & fossicking in Queensland, including in southern Qld.

To lawfully go detecting gold nuggets (and gold specimens) on such properties - a Qld Fossicking Licence is also required.

 

Unallocated State Land

The Qld Government webpage for "Fossicking Rules and Responsibilities" states: "If the land is "Unallocated State Land", you don't need permission to fossick unless:

  • there has been a native title determination over the land, or
  • the land has been ‘vested’ in another agency and used for a particular purpose."

"Unallocated state land (USL) refers to land above and below the high-water mark (HWM) that is not freehold land or land contracted to be granted in fee simple by the state; is not a road or reserve; and is not subject to a lease, licence or permit issued by the state."

The Qld Dept of Natural Resources & Mines previously reported that:

"There is a sometimes a misapprehension that there is a lot of unallocated state land or vacant crown land across the state. While there are a large number of parcels of unallocated state land, most are small in size and in odd locations. Other than a few occasional large parcels of land, the majority of land across Queensland is allocated either as freehold, leasehold, road, reserve or other tenure such as national park or state forest. Unallocated state land makes up less than 1% of Queensland land."

In June 2023 it was reported that there were "over 16,000 Unallocated State Land parcels" in Queensland.

The Qld Govt. Department of Resources (Lands Services) have recently advised that:  "As there is no list or register of available Unallocated State Land (USL) in Queensland - it is recommended that the departments FREE interactive online mapping service, Queensland Globe is accessed to allow you to search an area of interest and view all parcels of land with a tenure type of USL or SL in Queensland. This can be sourced in layers under "Planning Cadastre", by ticking "Land parcel tenure".

 
Brisbane Metal Detecting Club (BMDC)
The following information is published on the BMDC website:
“The Brisbane Metal Detecting Club (BMDC) is a non-profit organisation for metal detecting enthusiasts in Brisbane and surrounding areas. The club supports detectorists who specialise in the search for coins, jewellery and relics, as well as the infamous Australian gold nugget.
Together, the members have many years of experience in varying conditions in Australia and overseas, and are eager to share their knowledge and experience about detectors and detecting with anyone. BMDC members have access to the club's collection of helpful and educational library materials, including books, videos, maps, magazines, CDs and DVDs. Organised group trips to national goldfields and local areas of general detecting interest occur on a regular basis.

 

Books, Atlases, Online, etc.  
'Gold Prospecting’ by Doug Stone – reprinted in 2022, (192 pages) contains a section (26 pages) on goldfields in Queensland, including locations and old maps. Doug Stone has been writing prospecting books for decades, and has also authored a great range of 'Gold Atlas's' for several Australian states, including excellent maps.

    

 

A Prospectors guide to metal detecting in Australia - Gold & Ghosts’ - 2 Volumes for Qld (Volume 3 & Volume 4) by Mr. D.W. de Havelland (There are also 2 other volumes for Western Australia). These excellent/detailed books (containing numerous maps) have been out-of-print for decades, and are highly sought after.


     

Historical maps of various goldfields throughout Queensland - can be viewed online via the TROVE website. This excellent website also contains digitized historical newspapers - including reports on gold discoveries, prospecting & mining throughout Australia since the mid-1800's.

The archived website of the former Brisbane-based business of 'Treasure Enterprises of Australia' contained some excellent information on the locations and details of gold occurrences in Queensland.

The free  online database  Mindat.org  contains detailed information on minerals and their localities, deposits, and mines worldwide, including gold in Queensland.  Mindat.org has been collecting, and sharing such mineral information for the past two decades.

 

Queensland Gold Mining Leases  - Historical records held at the Qld State Archives commencing from 1871. This includes bound volumes of gold leases, including names of leaseholders and areas of leases. "Each lease in a volume includes the date of lease, name of the applicant, period of the lease and amount of rent, as well as a sketch and description of the area of the lease, and any transfers of the lease." Digital copies can also be requested.

'The Goldfields of Queensland - Charters Towers Goldfield' - a historical report published in 1899 (which has been digitized, and can be viewed online via the TROVE website) contains detailed information about the numerous gold mines that were operating around Charters Towers over 124 years ago, including old photographic images, and also details of the extent of workings and gold production results.

The 'Outdoors Queensland' website also contains some tips & resources for fossicking in Queensland.

The online ‘Prospecting Australia’ Forum , and also the online 'Gold Detecting and Prospecting Forum'  -  contains valuable information, and has many helpful/experienced members.

Based on my experiences with hunting gold throughout the mainland of Australia - the importance of doing extensive research on likely areas of potential for finding gold can not be under-stated. Sometimes the best areas to find gold are the hardest to get to, often away from any vehicular tracks, sometimes in/nearby rugged, undulating/hilly terrain. Besides using a modern pulse-induction Minelab detector - preparation, patience & perseverance are all a must-have to find gold.

Are you up for a challenge ?

 

Large Nugget Detected in North Queensland

It was reported in 2017 that a prospector,  using a Minelab Pulse-Induction (PI) detector,  found a  1.17kg  (37.7 Ounce)  gold nugget in a field near Charters Towers. The nugget was 15cm (6 inches) below the ground. The prospector stated:

“It was beneath some vegetation so it was a bit of a challenge to get to, but now I’m thinking maybe those roots are keeping some other big nuggets safe ready to be found another time.”

 

 

Aussie-made Coiltek GOLDHAWK coils

Aussie-made Coiltek GOLDHAWK coils

Aussie-made  Coiltek  GOLDHAWK  coils

The Minelab GPX 6000 detector has now been available for nearly 2 years. Many prospectors throughout Australia have re-visited goldfields, including their “fav” patches, that they considered “flogged” and then unleashed the GPX 6000 over such areas to find even more gold, including at depth.

The popularity of the GPX 6000 is not only due to its high performance, but also because it is of relatively light weight (50% lighter than the Minelab GPZ 7000), and it is very easy to use - even for “newbie” detectorists, and budding “prospectors”. It also costs approximately 20% less (a few thousand dollars less) than the Minelab GPZ 7000.

Now, there are even more coil options available for the GPX 6000 detector. In fact, there are currently more coil options available for the GPX 6000 than for the GPZ 7000.

With Minelab’s approval, long-time Aussie coil-maker ‘COILTEK’ recently released a range of 3 different sized Monoloop (“Mono”) coils for the GPX 6000. These are named the ‘Goldhawk’ series of coils.

The Coiltek Goldhawk coils (very pale tan coloured) are rated as waterproof to 1-metre depth, have a 2-Year Warranty, and include the following sizes/weights:

9 inches round - cost $609  (weighs 700 grams)
10x5 inches - cost $579  (weighs 575 grams)
14x9 inches – cost $639  (weighs 900 grams)

Feedback so far, including from many gold hunters throughout Australia, has been impressive as to how stable (smooth & quiet) the coils run, and how sensitive they are to all sizes of gold nuggets, with great depth capabilities.

Many people also prefer the elliptical shaped coils, for not only ease of use in confined areas/less-open ground/more vegetated ground, but also for better pinpointing capability than a round coil.

 

 

 

Gold Search Modes on the Equinox 900 & Manticore detectors

Gold Search Modes on the Equinox 900 & Manticore detectors

 

Gold Search Modes on the Minelab Equinox 900 & MANTICORE detectors

If you are not keen on spending several thousand dollars on a Pulse-Induction “gold-specific” metal detector, and would prefer to get an “All-Rounder” (coin/relic/gold) detector, at a fraction of the cost, that is lightweight, with discrimination & pinpointing capabilities - that you can use on beaches, and/or in parks, and/or in the bush including in gold-bearing terrain, or underwater – then Minelab have several great new options for your consideration.

Minelab recently released two new detectors - the Equinox 900 and the MANTICORE.

Both these 'VLF' detectors feature Simultaneous Multi-Frequency technology, including operating frequencies of between about 5 and 40 kHz, as well as the options of selectable single frequencies.

 

These two new Minelab detectors have a significant number of segments of Discrimination Scale. The Equinox 900 has 119 Target ID numbers (from -19 to 99), and the Manticore has 100 Target ID's numbers (from 0 to 99). By comparison the older Equinox 800 only has 50 Target ID numbers.

Interestingly, the Equinox 900 detector kit also includes two Double-D coils (the 11 inch, and 6 inch coils), whereas the Manticore currently only has an 11 inch Double-D coil available. Having  the Equinox 6 inch Double-D coil  is an advantage in terms of hunting small (sub-gram) gold nuggets, particularly in trashy areas (e.g. on old goldfields and nearby bush camps), and also in confined spaces to swing (e.g. in narrow gullies, including those highly vegetated, and areas covered in boulders or fallen timber etc.).

Both these new detectors also include excellent, low latency, wireless (Bluetooth) headphones. They also both feature a built-in Lithium-ion battery (within the handle), a built-in speaker, and LED flashlight (for nighttime use). They both only weigh about 1.3kg (The Minelab GPZ 7000 detector weighs about 3.3kg).

All new Minelab detectors have a 3 Year Warranty.

 

Both these detectors also have Search Modes suited for gold nugget prospecting.

The Equinox 900 has two gold search modes – designated as ‘Gold Profile 1’ (for “Normal Ground”) and ‘Gold Profile 2’ (for “Difficult Ground”), whereas the Manticore only has one gold search mode – designated as ‘Goldfield - General’ (suitable for benign to moderately mineralised ground).

Minelab explain these different Search Modes for the respective new detector as follows:

Equinox 900

“Gold Profile 1* — Normal Ground Gold 1 is suitable for searching for small gold nuggets in ‘mild’ ground. Most goldfield locations have a variable level of iron mineralisation that will require an ongoing Ground Balance adjustment, therefore Tracking Ground Balance is the default setting. The audio Threshold Level and Threshold Pitch is optimised for hunting gold nuggets. Gold 1 Multi-IQ processes a high frequency weighted multi-frequency signal, while ground balancing for mineralised soil.

Gold Profile 2* — Difficult Ground Gold 2 is best for searching for deeper gold nuggets in ‘difficult’ ground conditions. Gold 2 has a lower Recovery Speed, which will increase detection depth. However, more ground noise in more heavily mineralised grounds may result. Tracking Ground Balance is the default setting. The audio Threshold Level and Threshold Pitch is optimised for hunting gold nuggets. Gold 2 Multi-IQ processes a high frequency weighted multi-frequency signal, while ground balancing for mineralised soil.”

Minelab also state that when using the Equinox 900 in either of the two gold search modes, the user could typically expect the detection of gold nuggets to have a positive Target ID number, with a low number.

“Difficult Gold Areas — Hot Rocks ‘Hot’ rocks are commonly found in gold prospecting locations. These are rocks that are mineralised differently to the surrounding ground. A highly mineralised rock buried in mildly mineralised ground would be considered to be a hot rock. Hot rocks can easily be mistaken for gold nuggets. The Target ID can assist here, with hot rocks typically having a negative Target ID number and gold having a positive ID in the very low conductive range.”

 

Manticore

“Goldfield – General: suitable for small nuggets in benign to moderate soil mineralisation conditions.

Goldfield General Mode is for gold prospecting. Generally, gold nuggets are found in remote goldfields where the ground is often mineralised and targets are more sparsely distributed. For Goldfield General Mode, the default Audio Theme is set to Prospecting, providing a 'true' threshold tone which maximises sensitivity to weak target signals. When a target is detected, the signal volume and pitch vary proportionally to the strength of the target signal. Most goldfield locations have a variable level of iron mineralisation that requires constant Ground Balance adjustment, therefore Tracking Ground Balance is the default setting. Goldfield Mode is suited to finding smaller surface gold nuggets (and some larger deeper ones) in mineralised ground.”

 

Typical Target ID Numbers/Air-Depths for Gold Nuggets Recent air-depth testing (non-buried target) using both detectors (set on only medium Sensitivity), and with both coils used on the Equinox 900 - upon a very flat (5mm diameter) 0.27gram (sub-gram) nugget indicated air-depths of about 2 to 3 inches, with Target ID numbers in the range of about 15 to 20.

A sub-gram nugget detected using the Equinox 900 + Minelab Equinox 6-inch Double-D coil.

Equinox/Manticore Target ID numbers for gold nuggets can vary depending on several factors, including the size & shape of the nugget, and also gold purity, including the amount of any other metals present like silver & copper. Larger nuggets (more than a few grams) can indicate Target ID numbers of up to within the range of about 30 to 50.

 

It makes me wonder …..

(i) Will there be a future upgrade for the Manticore? to provide an additional gold search mode? i.e. similar to the ‘Gold Profile 2’ search mode on the Equinox 900 – that “is best for searching for deeper gold nuggets in difficult ground conditions”.

(ii) Will the proposed  Minelab M8 elliptical Double-D coil (8’ x 5.5” size) on the Manticore  detector provide increased depth capability in terms of detecting sub-gram gold? - compared to the Equinox 6 inch (‘EQX06’) DD coil on the Equinox 900 detector.

Minelab GPZ 7000 - a Deep Gold Getter

Minelab GPZ 7000 - a Deep Gold Getter

 Minelab GPZ 7000 - a Deep Gold Getter

The Minelab GPZ 7000 detector was released about 8 years ago in 2015. Costing nearly ten grand, this Minelab detector is suited for serious/deep gold hunting. Experienced users often refer to the GPZ 7000 detector as the "7"or "7,000" or "Zed".

Unique ZVT Technology
The GPZ 7000 is a unique detector as it features Minelab-Patented ‘Zero Voltage Transmission’ (ZVT) technology – which, technically, is different to both Pulse Induction (PI) technology and Very Low Frequency (VLF) technologies. The inventor of the patented Minelab ZVT technology, Dr Bruce Halcro Candy, explained the differences between VLF, and PI, and ZVT technologies as follows:

“Very Low Frequency (VLF) – VLF sinewave detectors have a major disadvantage in having to ground balance out, all of the soil signals simultaneously (all three soil components above).
Pulse Induction (PI) – PI metal detectors have a major advantage of not even detecting the major soil signal; the X component, but only the saline components, but this is mostly insignificant, and the VRM component, which is just a very small percentage of the X component.
This makes the capability of PI technology to ground balance far more accurate than VLF detectors.
A disadvantage of PI is its lesser ability to detect very small nuggets compared to VLF detectors.

Another disadvantage of PI is its capability at detecting very large nuggets compared to CW metal detectors, such as ZVT. CW means Continuous Wave and includes all technologies that do not have zero transmit periods (almost all technologies other than PI).

Zero Voltage Transmission (ZVT) – ZVT has the same major advantage as PI for ground balancing in not detecting the major soil component X, but has the same advantage of CW metal detector technologies compared to PI for detecting very large nuggets because ZVT is CW (unlike PI that is not CW), and also the same advantage as PI for being relatively insensitive to saline soils compared to VLF.”

So, in simple terms - you get the best of both worlds - ZVT technology has the same excellent ground balancing properties of Pulse Induction (PI) technology while retaining Continuous Wave (i.e VLF) technology's ability to detect very small nuggets - so you can find more gold of all sizes, including deeper, even in highly mineralised soils.

Advantages of the GPZ 7000 Super-D coils - compared to Monoloop coils for PI detectors
Conventional configuration Monoloop (“Mono”) coils, and Double D coils, would both not operate effectively with ZVT technology. Hence, Minelab invented the ‘Super-D’ configuration coils (sometimes referred to as a “DOD” configuration coil).

The Minelab Super-D coils consists of two symmetric D shaped receive windings (one on the left and one on the right), with a central, oval-shaped transmit winding. This Super D coils winding geometry provides a double audio response for shallow targets, and a single audio response for deeper targets.

The Minelab Super-D coils have also been designed to have minimal response to the impacts of scraping and knocks to the coil housing - which can cause annoying false signals during detecting e.g. some PI detector coils suffer from this.
The Minelab GPZ14 Super-D coil (which is actually 14’x13’ in size), and the bigger GPZ19 Super-D coil (actually 19’x18’ in size, and weighs 1.83kg), are also both waterproof to a rated depth of 1 metre. The GPZ 7000 detector control box & control panel are NOT rated as waterproof.

Other Features of the GPZ 7000
Unlike the GPX 5000 and GPX 6000 (and most other Minelab detectors), the GPZ 7000 features a concealed coil cable whereby the coil cable (and plug) is housed (internally routed) within the removable lower shaft.

Unlike the GPX 6000, the GPZ 7000 does not have a built-in speaker. However, the GPZ 7000 is supplied with a wireless ‘Audio Module’ speaker (WM12).

With 256 Noise Cancel channels, the GPZ 7000 has enhanced immunity against Electromagnetic Interference (EMI), and hence picks up less atmospheric noise, including from power lines, electrical equipment, and also other metal detectors operating nearby. There are two options to Noise Cancel - either via Auto Noise Cancel function (Default), or manually. Auto is the recommended setting, and may take up to about one minute.

Most people immediately notice the weight difference between the 7000 (3.22kg) and the younger Minelab sibling GPX 6000 (2.1kg) - with the 7000 being about 50% heavier than the 6000.
The use of a quality Bunji/Bungee/Bungy cord can effectively reduce the "swing arm-carried" weight of a detector by at least one-half (50%) e.g. so that the GPZ 7000's "felt weight" is comparable to the full weight of the GPX 6000.

Recommended Techniques for Achieving Optimal Performance
Like other Minelab detectors, good ground balancing techniques are crucial to getting the optimal performance capabilities out of the detector. The initial ground balancing technique for the GPZ 7000 IS DIFFERENT to the technique you should use for a Minelab Pulse Induction (P.I.) detector like the GPX series of detectors. Minelab recommend the following ground balancing technique for the GPZ 7000:

“Ground Balancing   VERY IMPORTANT
The best way to ground balance initially after switch on with the Quick Trak trigger depressed, is to sweep the coil in a typical side to side search mode at the expected operating height above the soil surface, e.g. 2–3 cm or whatever the soil saturation or terrain will allow, but at the same time move forward at slightly faster than normal walking speed, so as to cover as much different ground as possible in the first 10 to 12 seconds. The idea during this initial period after turn on, is to expose the detector to as much different soil data as reasonably possible to improve the
initial calibration.
IMPORTANT!   DO NOT ground balance using a coil up and down motion (like one would do using a PI detector) initially after turn-on with the Quick Trak trigger depressed. This does not give the initial calibration enough different soil information to calibrate optimally. If ground balance is required again sometime later (but without turning the detector off), ONLY THEN is the usual (PI type of) ground balancing up and down coil motion OK.”

Minelab Software Updates
There have been two software updates released by Minelab for the GPZ 7000.
The first update (released in 2015) related to a new auto ground tracking algorithm, and improved auto ground balance function.
The second update (released in 2017) featured an all-new ‘Ground Smoothing’ function as a primary enhancement. This function provided selectable noise filters that help deal with difficult ground, especially salty soils. A ‘Semi-Auto’ setting was also added to the ‘Ground Balance Mode’ to provide improved ground balance stability.

Yellow Ferrite Ring Ground Balancing
Minelab also recommended the use of their Yellow Ferrite Ring for optimal ground balancing.
Minelab stated:
“It’s very important to Ground Balance the GPZ 7000 using the yellow ferrite at the start of your detecting session. By doing this, any ferrite-like components encountered in the soil will not cause any false signal audio responses. The updated software shows the use of the yellow ferrite as part of the animated guide sequence when you follow the Quick Start/Quick-Trak process. (This is also a way to determine if a GPZ 7000 detector has the new software installed.)”

Accessories included with the Minelab GPZ 7000 detector
Accessories included in the Minelab GPZ 7000 box (in addition to the detector + Minelab GPZ14 coil) are:
Quick-Detachable Control (Guide) Arm + WM12 Wireless Audio Module + KOSS headphones + Pro-Swing 45 Harness + battery charger & charging cables.

Optional Coils
The Australian company ‘Nugget Finder’ (NF) recently released the Minelab-approved ‘Z-Search’ range of non-spoked coils, namely a 17x13" elliptical coil, and also a 12" round coil. These coils have a DOD configuration, a 3year Warranty, and are rated as water resistant to 1metre. These NF coils also include a Minelab lower shaft.


Several incredible gold nuggets have been discovered in Australia over the past 8 years using the GPZ 7000, including down to depths of about 1 metre, and no doubt yet more big nuggets will continue to be unearthed.