GMT, Does anyone use one

[azdigger]

HI All, It seems like when I ask a question about something to do with a GMT I get very few if any answers and I was just wondering if anyone on here even uses a GMT.
I use mine for Gold and meteorites. So far I have found Meteorites but no Gold as of yet, guess if I got out in the gold fields instead of the Meteorite strewn fields it might help.
Thanks

 

[moregold]

Hi AZDIGGER -- Since you have not received any responses, I will give you my two cents worth. I first started searching for gold nuggets about 15 years ago using the coin/relic Garrett GMH CX111. Did not find any gold so I bought a gold machine,a White's V/SAT(which I recently gave to a friend in NW Nevada) and started finding gold but it took me 9 months for my first nugget to show-up. Since I was getting dead serious about finding gold I then bought a Minelab SD 2100( which I still use) and added multiple Minelab and Coiltech coil for my toy's. During that period I bought a Gold Master 4 which I traded for the GMT(which I still use) when they came out. When The White's MXT I bought one for it multiple purposes which are great to use around old mining areas and ghost towns plus nugget hunting.
To get back to your question; yes there is at least one other person that uses a GMT but not exclusively. I have seen your posts on some of the Gold Forums. I'm not sure if you posed the question on them but if you did you probably got an answer such as" yes those VLF machines are OK but you really need one of the Minelab PI machines "! Finding gold nuggets is similar to coin/jewelry/relic hunting. Your success is generally related to having more than one detector with multiple coils. Having said that, the real key is to have a very good understanding how each machine works; how coils work and which combination of detector/coil is best for the field condition that you will be detecting. This has to be tied into doing your research. Are you going to search wood chip areas, soccer fields, trashy area and etc. For nuggets; what is the history of the area; how deep is the bedrock; what is the mineralization in the soil and etc.
In the area that you live in; between two meteorite fields and one which has produced a substantial number of nuggets; the GMT and MXT which I believe you said you had access too should do you well at least in Gold Basin. I have detected Gold Basin for years and prefer the Jimmie Sierra Gold Max for the GMT. I have a Sierra Hot Shot 12" coil which gathers dust in the closet. I have not detected Franconia for meteorites. For coin/jewelry etc., my preference for the MXT is the Sierra Big Foot coil but have others if needed.
A large percent of the serious nugget finders that I have encountered have both a PI and a VLF( GMT, GoldBug,etc")so they can maximize their finds by taking advantage of the pluses of the two types of systems and multiple coil selection. Don't feel that you are the only one with a GMT. ---- John W.

 

[Architex]

I have a GPX 400 and just ordered a GMT. Have not had the chance to use either in gold country as yet (soon), but I bought the GMT because of it's many recommendations from people who do use it. Plus it will have White's quality.

 

[azdigger]

John Thanks for responding. I have access to a Whites GMT (mine) a Whites MXT (my fathers) or an XLT (also my fathers)
He is not happy with the MXT for hunting meteorites as he has passed the coil over a find before I dig it and gets very little response. I would think maybe a tune up but he just got it back from the factory so I know that is not the problem,we are going to try it for coin and relic hunting and he has the XLT for coins. All I have right now is the stock coil on my GMT but for meteorites it has done a GREAT job and given me lots of confidence. I ain't made it to Gold basin to hunt gold and meteorites yet butI hope to fix that soon.
As far as a PI machine they are just to pricey for me to even consider even for a used one. so I will make do with the GMT.
Thanks

 

[moregold]

n/t

 

[moregold]

Hi azdigger -- The luck that you are not having with the MXT surprised me and stimulated me to do some air test with my MXT.Air test certainly are not represent the real world of detection in soils but can give you some idea of what to expect. Therefore I'm not giving any depths but just what the response was when a item was pasted by the coil.The MXT was set at lock ground balance; discrimination set at zero(0)and gain at about 3-4. The gain was set low based on the thought that if I could hear it there that anything higher would improve the response. Threshold was so it could be barely heard. The coils I used were the stock 950, a Excelerator 41/2"X 7" DD and the Sierra BigFoot 31/2"X18". The meteorites were ten Gold Basin stone chondrites varying in weight from 5 grams to 252 grams. The two gold nuggets tested weight 0.2 grams and 2.1 grams. The summarized results where:
950 coil --- In the jewelry mode all items gave a detectable and repeatable sound response. When I increased the discrimination to the preset mark( about 31/2) there was no response or a very broken res pose which I would not have dug. In the relic mode all items gave a response and there was no discrimination when it was increased to 7.In the prospecting mode with SAT at maximum all item gave a detectable response.
41/2"X 7" DD coil --- The response in jewelry mode was the same as the 950 coil. In relic mode it was the same as the 950 but on the two smallest items the response was iffy. In prospecting the response was the same as the 950 except the small nugget gave no detectable response.
BigFoot coil --- In jewelry mode it was the same as the 950. In relic the gold was detectable. The meteorites where detectable only on the right edge of the front 9"'s but fully detectable over the rear 9"s( the BigFoot coil is designed to give different responses for the front and rear on the MXT). In prospect mode all items were gave detectable responses.
When I increased the gain to +3 I had to decrease the volume on my Black Widow headphone as it was too loud and I have a serious hearing problem.
All of the meteorites tested were found either with my GMT and the GoldMax coil or with the Minelab SD2100 with varying coils up to the large UFO (18"X24"). Since the GMT operates at about 48kHz and the MXT at about 14kHv there certainly will be a variance in sensitivity to gold or meteorites but then each machine is designed for specific purposes.
In summary; The air test result needs to be verified under actual field conditions with mineralization, hot rocks and basalt. However, it looks like to me that the MXT should detect Gold Basin meteorites. What was interesting was how all three modes/coils reacted to the items tested. Looks like I may have to make a trip to Gold Basin to test the MXT there. I'll probably start out with the relic mode but select the coil based on terrain, vegetation cover and etc.. Hope this gives you some ideas to test and good luck. John

 

[azdigger]

I guess I should have said that he gets a responce but not as loud as I get with the GMT, but he fixed that today...He bought a GMT so we can hunt as equals and he will get the same responce as I use my boost setting as I am hunting meteorites.