Gold bars typically have their weight inscribed on them. Make sure the actual weight matches this inscription. Many gold coins and pieces will also have their weight stamped on them. Check that the weight is accurate.
Check the diameter and thickness of any gold coins you’re considering buying. The specifications for collectible coins can be found in numismatic guides or online. Gold bars are sold in many different sizes, but the size of a standard gold bar is 7”x 3 ⅝” x 1 ¾” and weighs 400 ounces or 27. 5 pounds. Determine the actual volume of irregular objects, such as rings, by placing them in a graduated cylinder accurate to . 1 milliliters(mLs). Place 20mLs of water in the cylinder and add the object you wish to test. Record the difference in water level. 1 cubic centimeter is equal to 1 mL.
24 karat gold has a density of 19. 3 grams per cubic centimeter. 18 karat gold has a density of 15. 6 grams per cubic centimeter. 14 karat gold has a density of 13. 1 grams per cubic centimeter.
Typical karat markings are 10K, 14K, and 24K Some counterfeit gold will have a karat stamp on it, but rarely have a manufacturer’s name.
Hold the magnet slightly above the gold piece. Observe if the gold is attracted to the magnet and if the magnet can pick up the piece of gold.
Get a glass large enough to fit the piece of gold, and fill it with water. Drop the gold piece into the water, and observe it.
Put on safety goggles and gloves before working the the nitric acid. Make a light, small scratch on the gold using a nail file. Use an eyedropper to apply one drop of nitric acid to the scratch on the gold. If the liquid turns greenish, the item is probably mostly another metal like zinc and plated with gold. If the liquid turns a milky color, the item most likely is mostly sterling silver and plated with gold. If you’re nervous about using nitric acid, you could try a vinegar test instead. While slightly less accurate than nitric acid, vinegar is a milder acid that will produce similar results.
Fool’s gold or pyrite will leave behind a greyish streak. Real gold will leave a shiny golden streak.
Pyrite has a density of 4. 8-5 grams per cubic centimeter Pure gold has a density of 19. 3 grams per cubic centimeter.
Real gold will not scratch a penny and can be scratched by the penny. Fool’s gold or pyrite will scratch a penny and cannot be scratched by the penny.
Always inspect your gold before making a purchase. Rent or invest in a safety deposit box or safe to protect your gold.
Expect mark-ups when purchasing coins or jewelry to cover the artistic or collectible value of the item. If the price of an item is below the market price for its weight you should avoid the purchase.
