Scratch testing is one of the oldest methods known to man for testing the karat of gold. In experienced hands, a scratch test is sensitive to within about +/- 1/2 karat or about 2%. In the hands of a novice, sensitivity is more likely to be about +/-1-2 karat. Kits come with instructions (see: Gold Scratch Test Instructions).
The complete kits are for testing gold, silver and platinum. They come with gold test needles, wooden case, test acids and a scratch stone.
For video instructions, see:
|Test9||9 needles (4, 6, 8, 10, 12, 14, 16K,18, 20K)||$174.99|
|Test5||5 needles (8, 10, 12, 14, 18K)||$129.99|
|TES-808.00||3 needles (10, 14, 18K)||$59.95|