By Steve Herschbach
The common test is to crush the rocks and pan the material to look for gold. This means you need to know the difference between mica, gold, and sulphides like pyrite when seen in the pan.
From the HANDBOOK FOR GOLD PROSPECTORS IN WASHINGTON By WAYNE S. MOEN and MARSHALL T. HUNTTING 1975:
"Many times the novice prospector is undecided whether the "yellow stuff" he is looking at is really gold or is something else. The yellow minerals that are most commonly mistaken for gold are pyrite, chalcopyrite, and golden-colored mica flakes. Pyrite, or "fool's gold," is heavy, but not as heavy as gold; it is hard and brittle and crushes to a black powder when hammered, whereas gold is soft (almost as soft as lead) and malleable and can be easily beaten into very thin sheets that are flexible (can be bent a number of times without breaking). Pyrite is soluble in concentrated nitric acid; gold is insoluble. Chalcopyrite, also sometimes mistaken for gold, is similar to pyrite in these properties. Pyrite commonly occurs as cubic crystals, but gold almost always is found in irregular shapes, and in those rare places where it does occur as crystals the crystals are always in intergrown masses.
Tiny golden-colored mica flakes sometimes look deceptively like gold, but the luster of mica is different from that of gold; mica has laminations that can be split with a knife; and mica flakes, like gold, are flexible, but, unlike gold, the flakes are elastic, so that when bent they tend to return to their original shape. Gold is malleable, but mica is not; when mica is hammered it breaks up into numerous tiny flakes. Gold is heavy,· but mica is light. Thus, when panned, gold becomes concentrated in the very lowest part of the pan, but mica will be washed out of the pan, although because of its flakiness, it does tend to segregate somewhat from other light minerals. Mica fuses with difficulty; gold, pyrite, and chalcopyrite fuse easily in a blowpipe flame (gold at 1063° C.); and gold when roasted is odorless, but the sulfides, pyrite and chalcopyrite yield sharp-smelling sulfur dioxide fumes."
Not super professional but that is why I like this video.... kind of how a lot of us might do it....
and a smarter, more efficient method using a "dolly pot".....
If the quartz has a lot of sulphides it was common in the old days to roast the material first to vaporize off the sulfur and other volatiles before panning.
From Gold From Pyrites & Other Sulphides By E.H. HILL 1890:
"Test for a Perfect Roast.—The object of roasting is to get rid of all the sulphur, arsenic, antimony, etc., that can be removed by the agency of heat, and to convert the iron, copper, &c., into oxides, thus freeing a portion of the gold and fitting the remainder for chlorination.
A practical test of roasting can easily be made in an ordinary frying-pan, first coating the inside with a mixture of chalk and water and well drying. Mix the finely powdered ore with about its own bulk of fine charcoal; this is needful only when arsenic and antimony are present; still it helps to get rid of the sulphur and can do no possible harm. If the ore contains much sulphide of lead (galena) or sulphide of antimony (stibnite, antimony glance), add some fine sand, as without this addition the mineral while roasting would soon fuse, cake together, adhere to the pan, and ruin the assay. When all is thoroughly mixed, put the pan on the fire; stir well with an iron wire till the glowing ceases and no more sparks are given off; the assay will then appear of one colour, yielding to the stirrer like dry sand. Guard against too high a heat at first. If the roasted mineral is then examined with a magnifying glass or panned off in the usual way, a quantity of gold will be found free, ready for amalgamation."
Note the process above may produce hazardous fumes. Use appropriate caution!
I have had this gold /quartz specimen for a number of years....and have not been able to figure out the gold weight using the simple formula I found on the internet. For those of you willing to take up the challenge I can give you the dry weight and submerged weight in grams. I have attempted it a few times but I always come up with a negative number for total grams in specimen. Not sure if it means I have under an ounce or not. So here we go...total dry weight is 242 grams....submerged weight ..and by the way I did it properly...is 71 grams. My estimate is 24 grams ...than it ended up 1.4 ounces.. Hopefully a few of you come up with more of an accurate number...
By pepeli ridge
hi there, I found 2 nuggets ,smaller one 10cm deep,larger nugget under a 10 kilo slab of rock and 5cm deep.1 meter apart
looks like lead, a few small quartz stones attached.
maybe old musket bullets or shotgun slugs ,melted in bushfire ?
metal is soft, gunmetal silver when rubbed and will tarnish over time. any idea! cheers ,Paul
I would appreciate any help identifying these items. The top item is heavy bronze and appears to be a buckle of some type. Looks as if it would have been riveted to leather. The middle item I have found several of. One on a Civil War campsite with two lengths of chain attached to each link. Appear to be a combination of iron links and a lead or pewter disc. The bottom item I also have found on several occasions. Has a small lever looking attached part. All were found on an old plantation site along with some Civil War relics.