Jade has been treasured for some 7,000 years for its unique luster, lovely color and impeccable toughness. This precious gem has always had special significance in many Asian cultures and can be compared to the West's admiration of diamonds and gold. For centuries, nephrite jade and jadeite were considered one and the same. It was not until 1863 that they were identified as different minerals with a similar appearance and properties. Nephrite is a tough rock comprised of intergrown crystals of minerals from the tremolite-actinolite solid solution series, part of the amphibole group.
Nifontovite is a very rare member of the borate family of minerals. Named for Russian geologist Roman V. Nifontov who discovered it in 1961, nifontovite is found in few locations worldwide, including Russia, Mexico and Japan. Mexico is producing the cleanest and largest specimens at this time. Typically, nifontovite is transparent and typically colorless or gray with a vitreous luster. A nifontivite gem, donated in 2009, resides in the Smithsonian's National Gem Collection.
Obsidian has been used since the Stone Age for tools, weapons and as an ornamental material. It is used in modern times for scalpel blades. Obsidian is formed by the rapid cooling of viscous lava due to volcanic explosions. It consists of the same minerals as granite but cools so quickly that they do not have time to crystallize. Obsidian has a glassy luster and is usually black or very dark green, but it can also be found in an almost colorless form.
Named for the German biologist Lorenz Oken. Specimens often found as “cotton ball” formations because the crystals are straight and fibrous and they radiate out in orb like structures.
Oligoclase is a member of the plagioclase feldspar group. Two oligoclase varieties, sunstone and moonstone, are prized for their phenomenal optical properties.
Olmiite was officially named as a new species in 2006. It is the Manganese dominant analog of poldervaartite. It is named after the Italian mineralogist Filippo Olmi. The only known location where olmiite is found is the N’Chwaning II mine, Kalahari field, Republic of South Africa.
Onyx is the dark brown to black variety of agate, a cryptocrystalline quartz. Since ancient times onyx has afforded gem cutters and carvers an excellent source for carving cameos, intaglios, and other jewelry creations. Inexpensive, abundant, and available in large sizes, onyx is also a favored stone when fashioning cabochon gems and beads.
While we often think of opal in terms of phenomenal play of color, this gemstone family is full of other unique and appealing members that have their own allure. Gems can be transparent, translucent or opaque and form in almost any color in many locations around the world. Get to know all the varieties of this unique family by looking at our fire opal, dendritic opal, hyalite, Caramel Spice Opal (TM), Morado Opal (TM), along with even more blue, pink and green varieties. With such an endless array, opal truly is the 'Queen of Gemstones'.
Opalite is a man-made opalescent glass. When opalite is placed against a dark backdrop, it takes on a luminous blue or pink glow. Blue opalite has even been confused for moonstone at times.
Orpiment is an arsenic sulfide that grows in small masses with lemon-yellow to brownish-yellow coloring. Its name comes from a Latin term meaning "gold pigment," as this mineral was once used to make yellow paint. This gem is photosensitive and should not be exposed to light for prolonged periods.
Orthoclase is part of the feldspar mineral family, one of the most abundant mineral families in the world. It is a common constituent in granite used for industrial purposes. For example, "Black Pearl" granite countertops are composed mostly of feldspar. While orthoclase, a potassium-rich feldspar, is better known to collectors, there is one variety that many are familiar with: moonstone, prized for its shimmering adularescence.
While sapphires have mesmerized gem and jewelry connoisseurs since the dawn of time, one fancy sapphire variety has a distinct allure and prestige all its own: padparadscha sapphire. Padparadscha sapphire derives its name from the Sanskrit padma ranga, meaning “lotus color,” for its resemblance to the famed lotus flowers of Sri Lanka, where the gem was originally found. Padparadscha sapphires traditionally must combine elements of pink and orange in one gem to rightly claim their padparadscha title, though the coloration requirements are highly disputed.
Literally translating as “landscape stone,” paesina pietra is an ancient marvel of nature. Created 40-50 million years ago, picturesque scenes that often mimic those seen in everyday life were formed within limestone rock. Seen in a variety of colors and an infinite number of designs, these sedimentary stones were created as the earth shifted, forming fractures in the limestone. Composed primarily of compressed limestone and clay that formed in seabeds, it was the infiltration of iron and manganese hydroxide that created their variety of scenic patterns and array of colors. Paesina pietra has been collected as an objet d 'art since the 17th century throughout Europe. Highly regarded as a decorative accent, the stones were displayed prominently in European royal courts, including those of France, Germany, and England.
Pargasite mostly occurs in a brown color, but has been found in greenish-brown to dark green and black. This gemstone was first found in Finland in 1814 and is named for its site of discovery. A member of the amphibole group, pargasite is closely related to hornblende. Some fine specimens of this rare gemstone have been faceted.
Pectolite has crystals that are elongated and flattened, but it more often occurs as acicular sprays or radially fibrous masses. It may be white, pale tan, or pale blue to greenish. Pectolite occurs widely in Canada, England, and the United States.
August's birthstone, peridot, is a relatively inexpensive, beautiful gem with a pedigree dating back as far as early Egyptians. Among its accolades, peridot can count being a favorite among royals and clergy, used to adorn everything from a queen's crown to a knight's sword. Peridot jewels were actually among Cleopatra's beloved treasures, though she believed them to be emeralds, as gems were then classified solely by color. Prized for its all natural, unenhanced range of colors, peridot is the gem variety of olivine and exhibits colors ranging from golden lime greens to rich grass greens.
Faceted petalite gems and specimens are prized by gemstone and mineral collectors. Petalite's name is derived from the Greek petalos (leaf), referring to its perfect cleavage. Colorless material is common, and large crystals have been mined. Other petalite colors include white to yellow or gray, yellowish green to light green and pink. Crystals range from transparent to translucent and are prized for their good clarity. Faceted gems aren't often seen due to petalite's cleavage planes.
Petrified wood is the fossilized remains of what once was wood. The material became petrified over time by the invasion of minerals into cavities between and within the cells of natural wood. Instead of decaying, the organic materials in the wood were replaced with minerals, primarily silicate of quartz, without changing the original structure of the wood.
Displaying gorgeous deep raspberry pinks, pezzottaite is a relatively new gemstone that has been subject to much confusion due to its similarities with red beryl. Pezzottaite has a variety of misnomer trade names including Madagascan raspberyl, raspberyl and raspberry beryl. Pezzottaite was first thought to be a new variety of beryl. Pezzottaite upon analysis was found to be a new mineral variety, with a trigonal crystal structure and that it contained cesium and lithium, which differed from beryl, making its trade names misleading.
A rare beryllium mineral, phenakite was named in 1833 from the Greek word for "deceiver," alluding to its similar appearance to quartz. Its crystals are predominantly rhombohedral, and less commonly short and prismatic. Phenakite's rarity, hardness, lack of cleavage and high clarity make it a great option for collectors.