Specific Gravity Specimen Test for Gold Content

Go down

Specific Gravity Specimen Test for Gold Content Empty Specific Gravity Specimen Test for Gold Content

Post  MS on Fri Jul 17, 2009 3:05 pm

Just wondering if someone could help me work out an approximate gold content in a specimen.
It is ironstone with lets say 20% quartz with gold showing freely from most sides.
Its weight is 25.1 grams dry and 20.3 grams suspended in water which gives a difference of 4.8 grams.
I worked out 14.62 grams gold if it was only quartz but not even sure if I worked that out correct.
I would expect the gold content to be less due to the heaver ironstone and it would be appreciated if someone who has some knowledge in working these things out could tell me how or let what the gold content should be.
It's not going to the dolly pot as it's too nice and will be for collection only and no I wasn't the lucky one to find it.
Regards Mark
MS
MS
Contributor Plus
Contributor Plus

Number of posts : 792
Age : 54
Registration date : 2009-03-17

Back to top Go down

Specific Gravity Specimen Test for Gold Content Empty Re: Specific Gravity Specimen Test for Gold Content

Post  gray.nomad on Fri Jul 17, 2009 6:51 pm

Hello Mark,
Try this. Very Happy
http://www.gold-nuggets.org/specific-gravity-test.htm

Congrats on your nugget. Very Happy
See you up them thar hills.
Frank
gray.nomad
gray.nomad
Good Contributor
Good Contributor

Number of posts : 107
Age : 75
Registration date : 2008-10-22

Back to top Go down

Specific Gravity Specimen Test for Gold Content Empty SG tests

Post  Pennyweight on Fri Jul 17, 2009 9:18 pm

Hi Mark,
the most difficult thing with SG tests is the specific gravity (or relative density) of the host rock. For every 1% you get it wrong, you will be 1% less accurate. Quartz varies a lot in density from 2.6-3 and iron oxide varies even more, 3.3-4.5. A mixture of both is a nightmare affraid . Often, a visual estimate or one with a high frequency VLF detector
will give you a reasonable idea of gold content. Best method is the dolly pot Rolling Eyes !
But, I have a copy of the excellent 'stab in the dark' method devised by the late Chris Hake. When I see you next, I'll give you copy. This relies less on accurate host SG and is surprisingly reliable. Cheers, Dwt
Pennyweight
Pennyweight
Seasoned Contributor
Seasoned Contributor

Number of posts : 143
Registration date : 2008-10-22

Back to top Go down

Specific Gravity Specimen Test for Gold Content Empty Re: Specific Gravity Specimen Test for Gold Content

Post  Guest on Sat Jul 18, 2009 12:24 am

does that work on large gold painted rocks PW?? Laughing

Guest
Guest


Back to top Go down

Specific Gravity Specimen Test for Gold Content Empty Re: Specific Gravity Specimen Test for Gold Content

Post  MS on Sat Jul 18, 2009 12:25 am

Thanks Frank and DWT.
I had a look at the site and have a better idea now and also thanks DWT I will take you up on that offer.
Regards mark
MS
MS
Contributor Plus
Contributor Plus

Number of posts : 792
Age : 54
Registration date : 2009-03-17

Back to top Go down

Specific Gravity Specimen Test for Gold Content Empty SG tests

Post  Pennyweight on Sun Jul 19, 2009 11:03 pm

Hi Mark,
no worries, will run off a copy for you. Steve, ya cheeky bugger Smile No, it wasn't 'gold painted rocks', it was gold painted lead! A friggin huge slab of it...thats why it convinced so many people! Plus the fact the rumour and photos were being spread by some serious 'heavy hitters' in the Triangle. These guys find over a hundred ounces each year, easy...and have found plenty of big lumps too. An analogy is like Kevin Rudd telling everyone that the Indonesians have invaded the Northern Territory (and showing photos). Just how many people would believe that on day one???? EVERYONE! There are still a few stubborn people who reckon the 300+ ouncer was real, even today! Cheers, Dwt
Pennyweight
Pennyweight
Seasoned Contributor
Seasoned Contributor

Number of posts : 143
Registration date : 2008-10-22

Back to top Go down

Specific Gravity Specimen Test for Gold Content Empty Re: Specific Gravity Specimen Test for Gold Content

Post  GoldstalkerGPX on Mon Aug 08, 2011 4:09 pm

Old thread re-kindled, hope this doesn't give anyone nightmares Shocked

Is there a limit on size that these conversions work? surely a formula works for any size....

I recieved an email today saying that this person has a quartz speci, weighs dry 0.91 & wet 0.20 They told me that they came up with a negative gold content...I laughed and said ya can't have a negative gold content, until I did some conversions and then I was laughing at myself aswell.....any idea's guys.

I know that some of you are doing this all of the time so would appreciate some thoughts or even better, an answer. Embarassed

Cheers
GoldstalkerGPX
GoldstalkerGPX
Contributor Plus
Contributor Plus

Number of posts : 1732
Age : 95
Registration date : 2009-07-27

Back to top Go down

Specific Gravity Specimen Test for Gold Content Empty Re: Specific Gravity Specimen Test for Gold Content

Post  davsgold on Mon Aug 08, 2011 10:31 pm

"weighs dry 0.91 & wet 0.20"

0.91g - 0.20g = 0.71g this will be the actual wet weight

Dry weight 0.91x1.9 = 1.729
Wet weight 0.71x3.1 = 2.207
2.207 - 1.729 = 0.478 grams of gold

Remember that to get the wet weight you can either place a beam across the scale and hang the specie in the water, this gets the answer you want, if you place the water on the scale and hang the specir into it yu then need to minus the dry weight from this number to get the wet weight.

Also make sure that there are no air bubbles stuck in or on the specie as this will also give a lighter wet weight.

cheers dave
davsgold
davsgold
Contributor Plus
Contributor Plus

Number of posts : 6082
Registration date : 2008-10-25

https://www.x-coils.com/

Back to top Go down

Specific Gravity Specimen Test for Gold Content Empty Re: Specific Gravity Specimen Test for Gold Content

Post  davsgold on Wed Aug 10, 2011 7:53 pm

davsgold
davsgold
Contributor Plus
Contributor Plus

Number of posts : 6082
Registration date : 2008-10-25

https://www.x-coils.com/

Back to top Go down

Specific Gravity Specimen Test for Gold Content Empty specific gravity-- Iwas wondering where do they get the 1.9 and 3.1 from?

Post  rmrussell on Mon Sep 03, 2012 8:37 am



Yes, i was wondering where they come up with the 1.9 and 3.1 figures when working out specific gravity?

Thank you . deaselanding

rmrussell

Number of posts : 1
Registration date : 2012-08-28

Back to top Go down

Back to top


 
Permissions in this forum:
You cannot reply to topics in this forum