Gold / Silver Testing Acid Tester Kit 14k silver & Testing Scratch Stone

Description

Silver and 14k Gold Testing Acid Solution (.5oz) + Test Stone
Silver Test Acid Solution
14k Gold Test Acid Solution
Includes one test stone that measures 2" (Size may vary between 2x1.5 and 2x3)
Silver testing via acid solutions is a classic way of testing silver items for their purity. This method is best used on scrap silver to be smelted due to the destructive nature of the testing but can be used on silver pieces to be worn if the testing if done in an inconspicuous spot.
PLEASE NOTE: Silver testing acids are made using NITRIC ACID that can harm the skin. Please exercise caution when using this method of testing, including proper protective eye wear and gloves. Nitric Acid can burn the skin and leave stains.
Procedures for Testing Gold
To test for the karat value of gold, platinum and silver, you will need the following materials and tools:
Black acid testing stone that is washed thoroughly with water prior to each test OR a needle file
Acid
Reference Gold - Either Gold Testing Needles or Verified Silver Pieces
Testing for 14K
Scratch or Rub the piece onto the test stone, leaving a visible deposit of gold on the stone. Next to this position, scratch the appropriate needle (14K) - if you do not have needles you can use a gold item that has a known karat value. Place a drop of the appropriate acid (same solution as the needle/gold item you have used) on the stone where the gold deposits are. If the gold is the same karat or higher, the acid will not affect the gold marks. If the gold piece is of a lower karat, the scratched deposit will dissolve and eventually disappear while the mark from the needle will stay.
When testing for potential gold plated items such as heavy necklaces and earrings, use a metal file to make a slight gouge in the piece. Place a drop of acid (the acid should match the karat value of the gold on the piece) onto the gouge. If the item is gold-plated, the acid will slowly dissolve the metal underneath. If the item is pure gold, no reaction should occur.
By repeated trial, the karat of the gold pieces can be determined to a close approximation.
(Caution: Many objects are marked 14K, but were fabricated prior to 1982 when it was legal to mark items 14K, but in reality the gold was 13.5K When testing 13.5K gold the 14K solution will not dissolve the scratch, but will make it lose its brightness and will turn it into a yellow-rusty color)
Testing for Silver
Rub or scrape the piece against a black testing stone. Rub or scrape a piece you know the purity of next to it. Be sure the marks are full and noticeable. Place a drop of silver testing acid solution on each mark. The acid will change colors depending on the purity; you should compare the reactions between the two marks to ensure accuracy. When testing on a piece of jewelry, create a small gouge in the piece in an inconspicuous spot on the piece. Place a small drop of acid on the mark, and observe the color change.
Fine Silver - Bright Red
925 Silver - Dark Red
800 Silver - Brown
500 Silver - Green
Note: The silver acid solution will dull the polish on the piece when tested directly on the piece, and may stain the piece.
Made in USA