Navette:  Oval shaped stone with a point on each end.  Also called marquis.

Niello:  This is a term you will find used to describe Sterling Siam pieces.  Nielloware is created by carving out areas of silver and baking sulfur/metals powder into the painted out areas creating the black enamel look.  Much of the Nielloware features figures from the Thai version (The Ramakien) of a prince, his wife, his parents (the King and Queen of Siam) and the evil king of Ceylon.

Obsidian:  Naturally occuring black stone which was often flaked into points for arrowheads.  Snowflake Obsidian features white to gray flakes which look like snow against a dark sky.  Obsidian is thought to help integrate the right and left hemispheres of the brain.  To clean your obsidian, avoid harsh detergents.  Wash with warm, soapy water and dry thoroughly.  Never clean ultrasonically and never steam clean.

Onyx:  Usually black in color, but there is also green onyx.  A type of opaque chalcedony.  Members of the onyx "family" include sardonyx which comes in black and white stripes, red and white stripes and brown and white stripes.  Black onyx has been believed for centuries to repel negativity.  Sardonyx is thought to foster luck.  To clean your onyx, avoid harsh detergents.  Wash with warm, soapy water and dry thoroughly.  Never clean ultrasonically and never steam clean.  Moh's scale of hardness:  6.5 - 7.

Opal:  Soft mineral composed of silicon and water, the water content sometimes being as high as 20% but is usually between three and ten percent.  Opal ranges from colorless through white, milky blue, gray, red, yellow, green, brown and black.  Precious opal shows a variable interplay of internal colors.  Opal may occur in the fissures of almost any kind of rock.  Peruvian opal (also called blue opal) is a blue-green stone found in Peru which is often cut to include the matrix in the more opaque stones.  An opal doublet is genuine precious opal which is bonded to a base layer for stability.  A triplet essentially is a doublet that is protected with a quartz crystal cap.  To clean your opal, avoid harsh detergents and hot water.  Wash in warm, soapy water and dry.  Never clean ultrasonically and never steam clean.  Moh's scale of hardness:  5 - 6.5.

Palladium:  White gold alloy.  Contains no nickel.

Parure:   (pah ROOR)  More than two pieces of the same design - a set.

Pate de Verre:  (Paht duh VAIR)  Molded colored glass used in jewelry, sometimes called poured glass.

Patina:  (pah TEEN ah)  Color change on the surface of metal resulting from age and exposure to the atmosphere.

Pave': (pah VAY)  Method of setting many small stones very closely together, paved.

Pearls:  Akoya pearls are saltwater pearls which makes them more valuable than freshwater pearls.  They also have more luster.  'AA' grade is nearly blemish-free with excellent luster.  'A' grade shows insignificant blemishes.  Luster is good.  'A/B' grade has surface blemishes which are easily seen.  Luster is moderate.  Moh's scale of hardness:  3.

Pear Cut:  Tear drop shaped stone.

Peridot:  (PAIR ih doe or PAIR ih dot) Naturally occurring gem form of the mineral olivine in a delicate green range of color tones caused by its iron content.  Said to help overcome anger and jealousy.  To clean your peridot, avoid harsh detergents.  Wash with warm, soapy water.  Never clean ultrasonically.  Never steam clean.  Moh's scale of hardness:  6.5 - 7.

Pietersite:  Naturally occurring stone named for its discoverer, Sid Pieters, who found it originally in Namibia, Africa.  It is a rare blue variation of tigereye.  Said to protect the eyes.

Pietra Dura:   (pee AY tra DOO ra)  "Hard stone."  Type of mosaic made of small pieces of stone which form a picture or scenic design.

Pinchbeck:  Alloy of copper and zinc used to imitate gold.

Plateria:  Spanish.  Place where silver is sold or a reference to silver jewelry or objects.

Plique a jour:  (pleek a ZHOOR)  Enamelling process in which the groundplate (the metal base on which the enamels are fired) is removed after firing.  The end result resembles stained glass with the translucent enamel framed in metal.

Pot Metal:  Base white metal, a tin and lead alloy, grayish in color, used in early 20th century costume jewelry.

Prasiolite:  Green Amethyst.  To clean your green amethyst, avoid harsh detergents.  Wash with warm, soapy water.  Ultrasonic cleaning is usually safe.  Never steam clean.  Moh's scale of hardness:  7.

Prong Set:  Stones held in place by metal claws or prongs.

Pyrite:  Pyrite forms naturally in cubes which have 12-sided faces and is found in igneous, sedimentary or metamorphic rock.  To clean your pyrite, avoid harsh detergents.  Wash in warm, soapy water and dry thoroughly.  Never clean ultrasonically and never steam clean.  Moh's scale of hardness:  6.