Test Nuggets

[Dean Mortimer]

I have lots of tiny pieces. Some the size of the ball in a ball point pen. Not sure if they are exactly 0.0025 could be less.

 

[Hawkear]

If you write 0.0025 as 0.XXXX then
The first X = a tenth of a gram
The second X = a hundredth of a gram
The third X = a thousandth of a gram
The fourth X = a ten thousandth of a gram.
Unless one had expensive electronic scientific grade scales probably costing thousands of dollars, it would be hard to measure anything accurately to the fourth decimal point.
My experience with the cheap electronic scales that claim to measure even to .01 of a gram is that they can't even do that very well as I have a reliable scientific beam balance to check them against.

 

[XLOOX]

If you write 0.0025 as 0.XXXX then
The first X = a tenth of a gram
The second X = a hundredth of a gram
The third X = a thousandth of a gram
The fourth X = a ten thousandth of a gram.
Unless one had expensive electronic scientific grade scales probably costing thousands of dollars, it would be hard to measure anything accurately to the fourth decimal point.
My experience with the cheap electronic scales that claim to measure even to .01 of a gram is that they can't even do that very well as I have a reliable scientific beam balance to check them against.

View attachment 16942

That is a beautiful piece of kit

 

[davsgold]

If you write 0.0025 as 0.XXXX then
The first X = a tenth of a gram ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, which is 10 bits to the gram, yes we find plenty like that with a 6000
The second X = a hundredth of a gram ,,,,,,,,,,,,,,,,,,,,,,,,,,,, which is 100 bits to the gram, good for panning
The third X = a thousandth of a gram ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, which is 1000 bits to the gram, I don't even think that's possible
The fourth X = a ten thousandth of a gram. ,,,,,,,,,,,,,,,,,,, which is 10000 bits to the gram, and thats less than a speck of dust

 

[kiwifred]

the mechanic from Dunolly has put his own vid up this week , you should get all the way to the end of that easy enough .

Can you name the Vid please

 

[Hawkear]

That is a beautiful piece of kit

Thanks and sorry to diverge from the topic somewhat but also have a little beamer. A portable one that I sometimes take with me on trips. It breaks down to store in the box. Once a jeweler who wanted to buy some gold from me seemed to be more interested in buying the scales. You can't be cheated with balance scales if you have your own set of weights.
In the background is a special pick presented to me by some good friends as a wedding gift when Gina and I got married. It has never turned a sod yet and am keeping it that way until I am well down in a hole and confident that a multi ouncer is just a few picks away even if it means going back home to retrieve the pick. I just like savoring moments and good things.

 

[woomera]

Can you name the Vid please

 

[clodmac]

If you write 0.0025 as 0.XXXX then
The first X = a tenth of a gram
The second X = a hundredth of a gram
The third X = a thousandth of a gram
The fourth X = a ten thousandth of a gram.
Unless one had expensive electronic scientific grade scales probably costing thousands of dollars, it would be hard to measure anything accurately to the fourth decimal point.
My experience with the cheap electronic scales that claim to measure even to .01 of a gram is that they can't even do that very well as I have a reliable scientific beam balance to check them against.

View attachment 16942

G'day Geoff
One of the issues with the cheap scales most of us use are is they are probably reasonably accurate once you get over half a gram or so , I suppose the problem with the very light weights under .01 is simply inertia . As I am the inquisitive type do you have weights of .01 gram or less that provide the inertia required to move the beam .
Cheers Clod

 

[clodmac]

Can you name the Vid please

G'day Kiwifred

The one previous to the vid put up by Woomera was the one I was referring to in the post .

Cheers Clod

 

[clodmac]

I have lots of tiny pieces. Some the size of the ball in a ball point pen. Not sure if they are exactly 0.0025 could be less.

G'day Dean

Probably the only way to figure it out with the scales most of us use would be to count out 10 or 20 bits that look to be the same size and weigh the whole lot at once , get the weight and then divide by the number, an average is close enough for the purpose .

Cheers Clod

 

[XLOOX]

G'day Geoff
One of the issues with the cheap scales most of us use are is they are probably reasonably accurate once you get over half a gram or so , I suppose the problem with the very light weights under .01 is simply inertia . As I am the inquisitive type do you have weights of .01 gram or less that provide the inertia required to move the beam .
Cheers Clod

The inertia in question is not in the weight but the balance beam as a function of its mass and quality of its bearing. The best ones, like in my old lab, actually have a mechanism for lowering the test weights onto their side of the pan to eliminate any dropping force affecting the reading. All enclosed in those lovely glass doors to prevent air currents and kept at a constant temp and sitting on a serious lump of marble to dampen vibrations

And all this discussion is completely off topic If you want a 0.0025g bit of gold clodmac, the way to make it was given much earlier- weigh a tiny bit, within the capability of your scales, flatten it out as much as you can, work out the area and cut it up.

And it wont make the slightest difference to your testing of sensitivity of an MD whether it is 0.0025g or 0.005g as both weights are beyond anything detectable that matters.

 

[clodmac]

The inertia in question is not in the weight but the balance beam as a function of its mass and quality of its bearing. The best ones, like in my old lab, actually have a mechanism for lowering the test weights onto their side of the pan to eliminate any dropping force affecting the reading. All enclosed in those lovely glass doors to prevent air currents and kept at a constant temp.

And all this discussion is completely off topic. If you want a 0.0025g bit of gold clodmac, the way to make it was given much earlier- weigh a tiny bit, within the capability of your scales, flatten it out as much as you can, work out the area and cut it up.

And it wont make the slightest difference to your testing of sensitivity of an MD whether it is 0.0025g or 0.005g as both weights are beyond anything detectable that matters.

G,day XLOOX

Thanks for explaining the scales and how they work and are operated , I didn't know about the purpose of the cabinet either .

I got a couple of little bits the other day off my mate that as far as my scales will show are around half a grain each
, I will keep one as is and see how much I can divide the other ,

I apologise for not staying on topic the intention was to ask if it was possible in the first instance , which it's not .

Cheers Clod

 

[Hawkear]

G'day Geoff
One of the issues with the cheap scales most of us use are is they are probably reasonably accurate once you get over half a gram or so , I suppose the problem with the very light weights under .01 is simply inertia . As I am the inquisitive type do you have weights of .01 gram or less that provide the inertia required to move the beam .
Cheers Clod

To answer your question, the smallest weight I have is .01 gram (10mg). It is enough to move the beams on both the balances I have. The beams and tray supports for each rest on knife edges made of Quartz or Onyx, to minimise friction in movement which makes them highly sensitive.
The flat weights in the image range from .5 gr (500 mg) to .01 gr (10 mg). I don't have any smaller as one of .001 gr (1 mg) would be only a tenth the size of the smallest shown and extremely difficult to handle and probably require scales of even more precision (and expense) for it to be useable.
Getting back to topic again, a nugget weighing 0.0025 grams would weigh just a quarter the weight of the smallest weight shown and because gold is 7 times denser than aluminium its size would be even 7 times smaller again. Thats smaller by a factor of 1/4 x 1/7 =1/28.
Of course, there are plenty of nuggets that are that small, but the issue is the actual difficulty of measuring and stating what their weights actually are when they are that small.

 

[clodmac]

To answer your question, the smallest weight I have is .01 gram (10mg). It is enough to move the beams on both the balances I have. The beams and tray supports for each rest on knife edges made of Quartz or Onyx, to minimise friction in movement which makes them highly sensitive.
The flat weights in the image range from .5 gr (500 mg) to .01 gr (10 mg). I don't have any smaller as one of .001 gr (1 mg) would be only a tenth the size of the smallest shown and extremely difficult to handle and probably require scales of even more precision (and expense) for it to be useable.
Getting back to topic again, a nugget weighing 0.0025 grams would weigh just a quarter the weight of the smallest weight shown and because gold is 7 times denser than aluminium its size would be even 7 times smaller again. Thats smaller by a factor of 1/4 x 1/7 =1/28.
Of course, there are plenty of nuggets that are that small, but the issue is the actual difficulty of measuring and stating what their weights actually are when they are that small.
View attachment 16954

G'day Geoff

Thank you for the reply , the precision of your scales is testament to the skill of those who engineered them at the time , and still extremely good for any practical purpose .
Staying on topic I got back to the 0.0025 test nugget and tried to figure out the best way to make one ,
Using all my precision tools and resources at home which include a 6 inch ruler , a hammer , a scribe , a few beer cans ' a pair of sharp scissors , a stanley knife and a bit of gold weighing about 0.01 give or take a few thousandths of a gram .

Utilising my skills developed in the agriculture sector ( shearing ) and construction ( concreting ) I am almost there .

There's a couple of pics attached that display progress to date , all that's left to do is divide the nugget in the lizards mouth into 4

I took on board your advice about the actual physical size of the test weights and got a couple beer cans that I had available and cut out a section that weighed close enough to a gram on my scales after a bit of trimming here and there , then I was able to figure out the best shape to divide it up . Which ended up being square as per the pic .

After sacrificing a couple of cans cutting them up with the scissors , I came to the conclusion the best way to demonstrate the outcome of the dissection would be with the pic below as a single pic with the outcome shown as the blue bit of tape about 2mm x 2mm .
The aluminium square weighing 1 gram is 60mm x 60mm thereabouts

The next step was to get the bit of gold weighing around 0.012 or so and giving it a smack with the hammer , although it's not quite square it looks to be close enough to 2mm x2mm , might need another tap to make it easier to cut up .

In the pics with the flattened nugget there is a natural nugget that was of similar size and weight to demonstrate the pre hammer treatment . Both bit's were found by my mate, the small gold wizard mentioned in a previous post .

I will test the couple of bit's when I can before I cut up the flattened nugget to see if there is a difference of flat vs round which may be possible , even given the small size .
Any recommended corrections to the methodology or outcome so far will be taken on board , I am not certain if the aluminium has been divided the right number of times .

Thanks to all those who have provided advice .

Cheers Clod

 

[grubstake]

G'day Geoff

Thank you for the reply , the precision of your scales is testament to the skill of those who engineered them at the time , and still extremely good for any practical purpose .
Staying on topic I got back to the 0.0025 test nugget and tried to figure out the best way to make one ,
Using all my precision tools and resources at home which include a 6 inch ruler , a hammer , a scribe , a few beer cans ' a pair of sharp scissors , a stanley knife and a bit of gold weighing about 0.01 give or take a few thousandths of a gram .

Utilising my skills developed in the agriculture sector ( shearing ) and construction ( concreting ) I am almost there .

There's a couple of pics attached that display progress to date , all that's left to do is divide the nugget in the lizards mouth into 4

I took on board your advice about the actual physical size of the test weights and got a couple beer cans that I had available and cut out a section that weighed close enough to a gram on my scales after a bit of trimming here and there , then I was able to figure out the best shape to divide it up . Which ended up being square as per the pic .

After sacrificing a couple of cans cutting them up with the scissors , I came to the conclusion the best way to demonstrate the outcome of the dissection would be with the pic below as a single pic with the outcome shown as the blue bit of tape about 2mm x 2mm .
The aluminium square weighing 1 gram is 60mm x 60mm thereabouts

The next step was to get the bit of gold weighing around 0.012 or so and giving it a smack with the hammer , although it's not quite square it looks to be close enough to 2mm x2mm , might need another tap to make it easier to cut up .

In the pics with the flattened nugget there is a natural nugget that was of similar size and weight to demonstrate the pre hammer treatment . Both bit's were found by my mate, the small gold wizard mentioned in a previous post .

I will test the couple of bit's when I can before I cut up the flattened nugget to see if there is a difference of flat vs round which may be possible , even given the small size .
Any recommended corrections to the methodology or outcome so far will be taken on board , I am not certain if the aluminium has been divided the right number of times .

Thanks to all those who have provided advice .

Cheers Clod

Who says craftsmanship is dead?!

 

[clodmac]

G,day XLOOX

Thanks for explaining the scales and how they work and are operated , I didn't know about the purpose of the cabinet either .

I got a couple of little bits the other day off my mate that as far as my scales will show are around half a grain each
, I will keep one as is and see how much I can divide the other ,

I apologise for not staying on topic the intention was to ask if it was possible in the first instance , which it's not .

Cheers Clod

G'Day XLOOX

The bits I got off my mate were about 0.2 of a grain , not half a grain as I have said above . The 0.5 grain nuggets are the ones I use now that are on the 5 cent piece pic that's on here somewhere . I put them all on my scales at once to check and ended up at 1.4 grains
My mistake

Cheers Clod

 

[XLOOX]

G'Day XLOOX

The bits I got off my mate were about 0.2 of a grain , not half a grain as I have said above . The 0.5 grain nuggets are the ones I use now that are on the 5 cent piece pic that's on here somewhere . I put them all on my scales at once to check and ended up at 1.4 grains
My mistake

Cheers Clod

Hi Clod,
You are well on your way. Gold beating isnt easy, especially for such a tiny piece. I suggest in order not to lose it in the process you glue it to the very flat anvil ( a vice anvil is perfect) with some soft glue ( not superglue) and use a flat ended punch and hammer to spread it.

Dont try to heat the nugget with a gas flame as when it is that small you will just blow it away.

You can heat it to ~350 C with a soldering iron, which will help, but then you cant use glue.

Have fun