This topic really interests me.
Everything from how the ancients
learned the craft of smelting ores
to the latest assayer techniques.
Ed
Assaying & Smelting of Ores
-
roc2rol
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Re: Assaying & Smelting of Ores
What is a simple field test to determine fools gold
from real gold?
Thanks
Ed
from real gold?
Thanks
Ed
-
Jim Hatt
Re: Assaying & Smelting of Ores
Hi Ed,
Good to see you back. I was beginning to wonder if you had gone off on an extended prospecting trip somewhere, and got yourself lost.
There several things you can do in the field to identify Fool's gold.
Most fool's gold is a form of Pyrite. A good way to identify it, is to poke it with the point of a knife, and see if you can crush it. Pyrite is very brittle and turns to white powder when you break it.
Gold will just get a dimple in it, if you do the same test.
Another simple test it to rotate the sample while observing it in direct sunlight. Fool's gold will "FLASH" at you from only one angle. Gold will "SHINE" from all angles.
Another thing to look for is shape of the suspect particle. If it has five flat sides to it (like a 5 sided stop sign, but not all sides have to be equal. One could be large with 4 smaller ones) throw it away.
Gold is always very irregular in shape. Even the smallest particle of it still looks like a nugget when magnified (unless it has tumbled a long ways in a creekbed).
I am sure Roy, and possibly some others may be able to add more simple tests, but these have always worked for me.
Jim
Good to see you back. I was beginning to wonder if you had gone off on an extended prospecting trip somewhere, and got yourself lost.
There several things you can do in the field to identify Fool's gold.
Most fool's gold is a form of Pyrite. A good way to identify it, is to poke it with the point of a knife, and see if you can crush it. Pyrite is very brittle and turns to white powder when you break it.
Gold will just get a dimple in it, if you do the same test.
Another simple test it to rotate the sample while observing it in direct sunlight. Fool's gold will "FLASH" at you from only one angle. Gold will "SHINE" from all angles.
Another thing to look for is shape of the suspect particle. If it has five flat sides to it (like a 5 sided stop sign, but not all sides have to be equal. One could be large with 4 smaller ones) throw it away.
Gold is always very irregular in shape. Even the smallest particle of it still looks like a nugget when magnified (unless it has tumbled a long ways in a creekbed).
I am sure Roy, and possibly some others may be able to add more simple tests, but these have always worked for me.
Jim
-
roc2rol
- Posts: 825
- Joined: Thu Feb 04, 2010 8:58 pm
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- Location: Dutch's Ditch, AZ
Re: Assaying & Smelting of Ores
Very cool tips, Jim !
I did the dimple test on this quartz ore I got
when I went to Wickenburg.
By golly I do believe it to be the real stuff!
It was purchase I made.
I think I done good!-- as far as a great sample goes!
I was reading account of how the early prospectors,
even the ancients, used a stone,
(probably a piece of flat black jasper or something similar)
to do a streak test to check for the purity of the gold.
It was called a touchstone
Now here probably a silly question>
but what color does gold streak?
Ed
I did the dimple test on this quartz ore I got
when I went to Wickenburg.
By golly I do believe it to be the real stuff!
It was purchase I made.
I think I done good!-- as far as a great sample goes!
I was reading account of how the early prospectors,
even the ancients, used a stone,
(probably a piece of flat black jasper or something similar)
to do a streak test to check for the purity of the gold.
It was called a touchstone
Now here probably a silly question>
but what color does gold streak?
Ed