Tuesday, March 27, 2012

Metals Part 1 - Gold

When you buy jewelry, are you aware what metals are used and what you are essentially paying for? Why are some jewelry extremely cheap and others more expensive even though they look similar? For the next couple of weeks I'd be blogging about this and hopefully provide some answers to your questions.

Today, let's begin with GOLD.

Carat is the measurement of gold content. (Please note that the measurement of diamonds and gemstones, even though the term carat is used, are different measurements from gold). 24k gold is 100% gold. However, 100% gold is too soft to make into sturdy jewelry so other metals called alloys are used. Different metal alloys used will give the final appearance and colour.

Now back to carats... also seen as ct, kt or k. 14k gold is 58.5% pure gold or 585 parts gold per 1000. 18k is 75% pure gold or 750 parts gold per 1000.

Nowadays, gold is available in several different colours: yellow, white, rose, bronze, red and even lime gold! The difference in colour is determined by the metals used in the alloy mix.

Yellow gold - pure gold mixed with copper or zinc.
Rose gold - pure gold mixed with copper.
White gold - pure gold mixed with silver and palladium. White gold finish is greyish in colour so is usually coated (called plating) with a silvery white metal called rhodium to make it look whiter. Rhodium is very hard and sturdy, part of the platinum family and one of the most costly of metals.

Nickel was used traditionally in white gold but caused allergies in some people so is no longer added to white gold.

Gold filled is also known as "rolled gold." It is a solid layer of gold bonded with heat and pressure to a bass metal such as brass, and sometimes to silver though not as common nowadays.

High quality gold filled pieces look exactly like 14k gold. All 12k and 14k gold filled pieces have a stamp on it for identification. 12k GF and 14k GF. They have to meet the 1/20 minimum requirement. Gold filled pieces are 50,000 to 100,000 times thicker than gold plating. Even with daily wear gold filled jewelry can last from 5-30 years.

Gold plating is a thin layer of gold deposited onto the surface of another metal such as silver or copper. Needless to say, this will wear off quickly.

At Rebecca Yam Jewelry, I only use gold filled findings (wires, rings, hooks, clasps and ear wires) which is why my pieces cost a little more. Not only are you assured your pieces are one-of-a-kind (OOAK), you now know that I used good quality materials as well!

See you next Monday for more on metals, specifically SILVER.