Tuesday, June 5, 2007

Testing the Quality of Gold

All that glitters is not gold, and you should know how and when to test the quality of gold jewelry. Gold quality varies throughout the world and small differences in gold content can equate to a large difference in value for the collector or investor.

Jewelry markings indicate the parts per thousand of gold to base metals which are added for strength and durability. 24K gold is the purest form with 1000 parts per 1000 and a quality mark of 1000. 24K gold is rare in jewelry manufacturing due to the fragile nature of pure gold, and the prohibitive cost associated with pure gold.

22K gold is the second purest form with 916 parts per 1000 and a quality mark of 916. 22K gold is encountered on occasion when handling vintage jewelry; however it is rarely used in modern jewelry manufacturing.

18K gold is the standard for high quality jewelry throughout the world, with 750 parts per 1000. 18K gold carries a quality mark of 750. 18K gold is very pliable and will often bend with the slightest pressure. Great care should be taken when handling 18K gold jewelry.

14K gold is the most common form of gold on the market today, with high quality and lasting durability. 14K gold contains 585 parts gold per 1000 parts and carries a quality mark of 585. 14K gold is almost always marked 14K or 585 on modern jewelry.

10K gold is affordable, durable, and the most common form of gold jewelry on the market today. 10K gold contains 416/417 parts per 1000 with a quality mark of 10K, 416, or 417. Do not confuse the markings with the common markings on gold plated jewelry of 1/20 10K.

The basics of testing jewelry for quality have remained unchanged over time. Basic testing supplies include an Arkansas test stone and various test acids designed for jewelry testing. Advanced collectors and jewelry shops often carry an electronic tester for faster results; however electronic testers can present problems such as dead batteries. The tried and true methods are simply the most reliable over time.

Always wear protective gloves and goggles when testing the quality of jewelry. Always test jewelry in a well ventilated area and avoid breathing the fumes. Remember, testing solutions are acids and the utmost care should be used while handling and storing test equipment.

To test the quality of gold, gently brush the piece against the Arkansas stone to remove metal flakes and expose fresh metal. It is always best to test the piece in an inconspicuous place such as the inside of a ring. Place a small amount of test fluid on the flakes and note any reactions. If there are no reactions to the fluid the gold content is the quality tested or higher, repeat testing using the next higher test fluid until you are certain of the quality.

Testing solutions should be changed every 3 months to ensure accurate results. Keep all testing supplies away from heat, direct sunlight, and children at all times. If you have placed the test fluids on the jewelry itself, use a neutralizer and clean the piece prior to storage to prevent damage. Test acids will continue to react with pieces for an extended period of time if the acids are not neutralized!

Editor: aikencoins
Eric Murphey, owner of aikencoins

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