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Fakes & Fraudsgold plaque..?..
4th Dec 2012 00:32 UTCDermot Walsh
Thank you in advance
Seasons Greetings and Best Wishes
dermot
4th Dec 2012 01:55 UTCgoldguy24k
Newbee needs help. I can email photo, 3mgs, Jim
4th Dec 2012 02:13 UTCPaul Brandes 🌟 Manager
4th Dec 2012 10:50 UTCRock Currier Expert
4th Dec 2012 13:12 UTCOwen Lewis
If you find conc HNO3 hard to source (as it is, privately, in the UK now) you could check its SG, if you have or can borrow a scale that is accurate to 2 decimal places when measuring in carats (the smaller the object the more accurate one's scale needs to be to get a reliable SG). If you get an SG of 10.40 or higher, the chance of 9K gold is good. Pure gold (24K) is 19.32. The SG's of the several karat standards of gold alloy are actually not precise because of the the ratios of the base metals in the alloy are not fixed - only that of the gold content - so samples of any of the alloys may have an SG that varies within a small range.
The one you should look out for is brass (an alloy) which will have an SG in the range 8.4 - 8,7.
A particularly dangerous trick is pure lead flashed with gold which will have an SG of 11.34 or a little more, depending on how thick the gold covering is. Some 50 years ago, when Aden was a significant duty-free port and a port of call for tourist ships, gold sellers would go out to the ships in small boats, selling bars of 24K 'gold' to the tourists. The top side of these would bear the stamp of some prestigious institution. To show that the bars were solid, the traders would slash the base with a strong knife, which would (as fine gold does) open up almost as easily as cheese, showing no change in colour. Some tourists would have a proper assay (using nitric acid) done ashore and the stuff would pass with flying colours. However, cut a bar though and the gold on the top and sides would be revealed as no more than about 1mm thick in gold, and maybe 5 times that thickness in the base. The heart of the bar being pure lead.....
14th Apr 2013 04:48 UTCFranklin Roberts
14th Apr 2013 19:55 UTCTim Jokela Jr
15th Apr 2013 00:49 UTCMark Stanley
SherrGold Ltd. operated the MacLellan mine near Lynn Lake, Manitoba in the 1980's. Lynn Lake is about 1000 km northwest of Winnipeg, Manitoba, Canada.
15th Apr 2013 01:05 UTCDermot Walsh
regards
dermot
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Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2024, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: March 28, 2024 10:07:14