There are some at-home kinds of tests you can do to see what kind of material your jewelry is made of.
If you want to know if the stones are real, take your piece to your local jeweler. He or she can give you the answer.
If you want to know what kind of metal was used, check for hallmarks which are inscribed on the back of your jewelry.
AMBER: You can stick a hot needle into an inconspicuous spot. If it emits a pine odor, it is amber. However, some artificial amber being manufactured in Russia also includes small bits of genuine amber. If your needle hits one of those spots, it will also smell piney.
GUTTA PERCHA: Black or brownish in color and very lightweight. When rubbed briskly on a piece of cloth, you will have the smell of burnt rubber.
JET: Onyx, glass, bog oak and gutta percha can all be misidentified as jet. To do the following test, you will have to be very careful so you do not ruin your piece of jewelry. If you rub the piece across concrete, it will leave a brownish black mark if it is true jet.
PEARL: Rub them against your teeth. Real pearls will feel gritty. Imitation pearls are smooth. Cultured pearls are not imitation and will test as "real" pearls.
BAKELITE: You can perform the hot needle test on Bakelite. It will smell like carbolic acid. You can also dip a Q-tip into 409 Cleaning Spray and touch it to the back of your Bakelite. If the Q-tip shows a yellow discoloration, it is probably Bakelite.
CELLULOID: You can do the hot needle test. It should smell like camphor.
TORTOISE SHELL: You can do the hot needle test. It should smell like burning hair.
MISNAMED MATERIALS:
Alaskan Diamond: Actually rock crystal
Arizona Diamond: Actually rock crystal
Arkansas Diamond: Actually rock crystal
Arizona Ruby: Garnet
Belas Ruby: Spinel
Cape Ruby: Garnet
Cornish Diamond: Rock crystal
Goldstone: Manmade aventurine
Herkimer Diamond: Rock crystal
Siberian Ruby: Tourmaline
Smoky Topaz: Smoky quartz
African Jade: Opaque grossularite
Black Jade: Dyed Serpentine
Malaysia Jade: Dyed translucent quartz
Mountain Jade: Dyed dolomite marble
Serpentine Jade: Chrysolite
Yellow and Olive Jade: Serpentine