Metal detecting tips

WEIGHING PRECIOUS METALS

Bearing in mind that a piece of jewelry's value is relative to the labor it takes to create the individual item. However, the weight of a piece of gold or silver jewelry is a factor that helps to determine its value. It is important because it is an indication of the amount of fine gold in an item of jewelry. Grams (g) and pennyweights (DWT) are the units of weights most commonly used in weighing gold. Gold and silver are almost always weighted in the troy (t) system of weights where one pound troy (t) equals twelve troy ounces and twenty pennyweights equals one troy ounce. The following table summarizes useful weight conversions.
• 1 gram (g) = 0.0032 oz t
• 1 pennyweight (DWT) = 1.555 g = 0.05 oz t
• 1 troy ounce (oz t) = 31.103 g

Now that we have the weights in place, we must now find the percent of pure gold (24k) in the piece. To arrive at that we use the following formula.
24 karats (k) is 100% pure gold. 24/24
10 karats is 10 parts pure gold to 14 parts alloy. To arrive at the percent we use 10/24, therefore divide 10 by 24 which give us .4166 percent of pure gold.
• 10k = .4166%
• 12k = .50%
• 14k = .5833%
• 18k = .75%
• 24k = 100%

To put all this to use we will use a 14k ring that weighs 9 g. We need to look at the morning paper or go on line and get the value of gold or silver. Precious metals are always priced by the troy ounce. Today's spot price is $318.40 per ounce. Divide that value by 31.103 (the number of grams in a troy ounce). $318.40 by 31.103 (g) = $10.2369. Round that off to $10.24 per gram. Now we get the percent of pure gold in the 14k piece, which is .5833%. To get the value of the pure gold take $10.24 multiply it by .5833 gives us $5.97 per gram.
The ring weights 9g so we multiply $5.97 by 9 giving us the value of gold in the ring, as $53.73.