Gold

 

Gold Quality

Gold’s purity is measured in "karats".  24 Karat gold is pure gold, but its purity means it is more expensive and less durable than gold that is alloyed with other metals.

 

Karats                                 Percent
(parts of gold per 24)      (parts of gold per 100)
     24 Karat                            100 percent
     18 Karat                           75.0 percent
     14 Karat                           58.3 percent
     10 Karat                           41.6 percent 

 

Gold Weight

The weight of gold or gold articles is usually expressed in troy ounces and/or pennyweight (dwt)

1 Troy ounce = 1.097 ordinary ounce
1 Troy ounce = 20 pennyweight (dwt)

The "d" in the traditional symbol for pennyweight (dwt) is from the Latin denarius, the small Roman coin which was the equivalent of a penny.

 

Gold Color

Yellow Gold is alloyed with silver and copper. It is the most frequently used type of gold there is.

White Gold is alloyed with a large percentage of silver and is therefore more expensive than yellow gold. White gold is highly reflective and not subject to tarnish.

Rose Gold is alloyed with copper and silver.

Ex: 14kt yellow gold is 58.3% gold, 30% silver & 11.5% copper
      14kt rose gold is 58.3% gold, 9% silver & 32.5% copper

 

Gold Markings

By U.S. law, every gold article must have a karat mark. In addition to the karat mark, every piece of gold jewelry should be stamped with a hallmark or trademark of the manufacturer.


Gold Regional Preferences

Each part of the globe has very different expectations of what "gold" is.

United States       14karat/10karat
European Union    18karat/14karat
Mid-East              22karat/18karat
Far-East              22karat/18karat/14karat
10 karat gold in the U.S. is very common and an acceptable alloy. Other parts of the world do not recognize or accept jewelry marked 10K as precious.

 

Gold-Plated versus Gold Filled

Gold-plated jewelry has a thin layer of gold that has been applied to any base metal item by means of an electroplating (or dipping) process.  

Gold-filled refers to stock material which is made by combining a layer of gold to a layer of base metal.  The thickness of the gold layer will determine the percentage of gold by weight.  It may be 5%, 10%, 15% or 20% gold.

 

 

 

 

Silver

  

Silver Quality

Fine silver in its natural state, 999/1000 pure, is almost as soft as gold, too soft an element for practical jewelry. To make it workable, an alloy such as copper is added. The following are the more common silver alloys:

 

Sterling Silver - A mixture of 92.5% silver and 7.5% metal alloy  Sometimes jewelry made of this metal mixture is marked .925, to indicate that the
                        metal is at least 92.5% pure silver

Mexican Silver - 90% - 99% pure silver

Coin Silver - 90% pure silver and 10% metal alloy

German Silver or Nickel Silver - A silver white alloy consisting of copper, zinc, and nickel

Vermeil - Sterling Silver electroplated with karat gold