SILVER TEST NEEDLE, 5 PRONG SET 999, 975, 950, 925, 900

5pc set of SILVER test needles (999, 975, 950, .925, .900 ) is used with test stones and testing solutions to determine the contents of silver in item being tested.

Fineness % Silver Typical Use .999 99.9% Fine silver bullion, bars, coins .975 97.5% High-grade jewelry alloys .950 95.0% Argentium or high-silver jewelry alloys .925 92.5% Sterling silver (by far the most common jewelry alloy) .900 90.0% Coin silver, older coinage, some jewelry