The contemporary carat system for classifying gold jewelry arose from the Byzantium Era where their unit of currency, the solidus, was separated into 24 keratia. Pure 24-carat gold is too soft for use in jewelry and must be alloyed with silver, copper or bronze to strengthen its durability for long-lasting wear. In Europe, 18k gold is the standard, also called '750' denoting 75% gold. In the United States, it is more common to see 14k gold used in jewelry production. This represents slightly more that 50% pure gold with a European grading of '585' or 58.5% gold. Gold is considered solid gold at 10k, '417' Europen scale meaning 41.7 % gold. Anything less than 10k cannot be sold under the label of 'gold'. When buying a piece of gold jewelry, look for a quality mark and a trademark or hallmark stamped somewhere on the piece of jewelry. This will ensure that the buyer is purchasing genuine gold jewelry of the caliber it is marked with. These stamps are under strict control and will guarantee the validity of the piece for purchase. Gold exists in a variety of colors, depending on the metals it is alloyed with. Yellow gold is composed of silver, copper and gold. If copper is the only metal alloyed, the gold will have a pink sheen or pink gold. When platinum, palladium, zinc and copper are alloyed with gold the result is white gold. Green gold includes zinc, copper and silver.

The pricing of gold is based on caratage, design, craftsmanship and gram weight. Gram weight and caratage tell the buyer the quantity of gold in the piece of jewelry but the construction and design are essential factors in determining its value. Each piece of gold jewelry is unique and original and, if properly cared for, will last a lifetime.

Inspect the quality of the construction of the piece when making a purchase. Clasps, fasteners and working catches are all very important to the value of the jewelry. Be aware that soldering marks should not be visible on the backs of pins or earrings and the posts should be very secure and sturdy. When examining gold chain, it is advisable to lay it on a flat surface and ascertain that the links are intact, without kinking or bending.

Gold jewelry should never be exposed to chlorine, it can weaken the structure of the metal and ultimately end in breakage of the piece. Gold can become scratched and dented when treated harshly, store the jewelry in a soft cloth when it is not being worn. A cleaning solution of lukewarm soapy water will brighten your gold jewelry or bring it to a jeweler to have it steam-cleaned. Use a chamois or soft cloth to polish, dry and shine the piece. Gold does not react well with dust, moisture, make-up or perspiration.

If a weakness in the jewelry becomes apparent, bring it to the jeweler for repair immediately.