Larimar is a rare blue to green variety of pectolite, a mineral prized mainly by specimen collectors. While pectolite may be found in several locations, including Canada, England, and the U.S., larimar is found only in the Dominican Republic. This unique blue gem formed from volcanic activity millions of years ago that created the Caribbean island of Hispaniola. The most prized larimar exhibits sky blue color with a white pattern throughout, reminiscent of sunlight dancing on the floor of a pool. This gem was named by its discoverer for both his daughter, Larissa, and el mar, the sea.
Larvikite is a feldspar-rich igneous rock, called a monzonite and is named for the town in Norway where it was found. One characteristic of this stone is its blue sheen or labradorescence, caused by the presence of interlocking feldspar crystals within the structure of the stone. Through the wonders of nature, each polished gem has a sheen that sparkles with deep silver tones. Usually, this stone is used in ornamental and decorative purposes.
Also known as scoria, lava rock is formed from solidified volcanic lava. A defining feature of this rock is cavities caused by trapped gas bubbles. Unlike pumice, however, lava rock does not float on water. The unique look of this highly porous rock, along with its relatively light weight, makes it popular for jewelry and ornamental carvings.
This mineral species can be opaque to crystalline transparent. The color of lazulite ranges from medium to dark greenish blue to violet blue and is often mottled with white. When fashioned into gems, finished stones typically weigh less than 5 carats. A separate mineral species, lazulite should not be confused with lazurite or azurite.
Lazurite is a richly colored blue mineral primarily seen in cabochon gems or carvings. Lazurite is a major component of lapis lazuli, giving the stone its brilliant blue color. Lazurite crystals are rare, as the gem is most commonly found in massive form and rarely as well-formed crystals.
Lepidolite is a beautiful lithium-rich member of the mica mineral family. Violet to pink in color, lepidolite has a scaly appearance seen in many specimens. This gemstone is not commonly known to be faceted and is primarily used in ornamental and decorative pieces.
Liddicoatite is a calcium-rich lithium species of tourmaline named in 1977 in honor of noted gemologist Richard T. Liddicoat. Gems may form in green, pink, red, blue and purple colors, sometimes with internal multicolor banding and zoning. Large crystals are often sliced to display their natural multicolor designs.
Limestone is composed mainly of calcite and occurs in thick extensive, multiple layers. It is formed in shallow seas from a combination of calcium carbonate or the accumulation of shells and skeletons of calcareous marine organisms. Limestone is abundant and is very important commercially as it has a number of different uses as a building stone, cement and as a raw material in the glass manufacturing process. Limestone that is recrystallized under heat and pressure becomes marble.
Limonite gets its name from the Greek words for “marshy lake” because it is found in marshes. Limonite is a mineraloid that contains varied amounts of goethite and hematite, forming from weathering of hematite, magnetite, and pyrite. It is often found as a pseudomorph as it replaces other minerals.
The shell of the Pteria penguin, better known as the penguin's wing oyster, have a wing-like extension on one side of the shell is called “Mabé gai” in Japanese. The name “Mabé pearl” is inspired by this reference. The shells of the Pteria penguin and the Pinctada maxima are used to create blister pearls. The Haliotis variety of Abalone has also been used to create “Mabé pearls”. A plastic or wax half or three-quarter spherical or pear-shaped or heart-shaped nucleus is glued to the inside of shell. After two or three years of nacre growth the blister pearl is cut out of the shell. The nucleus is then removed and filled with resin and is backed with mother-of-pearl. The sizes range from 12mm to 25mm. They are more affordable than true cultured pearls.
The Madeira name comes from the Brazilian word meaning ‘wood’ or ‘wood colored’. Most madeira citrine comes from heating amethyst with a brownish core to get the warm yellow or orange color. The primary sources come from the Brazilian state of Rio Grande do Sul, Uruguay, Zambia, and Madagascar.
Magnesite, a member of the calcite mineral group, is often found in massive form, as well-formed transparent crystals are rare. Pure magnesite crystals are colorless, and any impurities present affect their color which is typically light yellow to brown or gray. Magnesite has perfect cleavage in three directions, making faceting extremely difficult. Faceted gems are often found in private collections or museums.
Malachite is generally opaque and comes in a vivid bluish green to green color. It is usually banded in two or more tones of green and may have a subtle sheen. This gem is a secondary copper mineral and is commonly found in conjunction with azurite, a bold blue copper carbonate mineral. A mix of the two minerals is often called azurmalachite.
Marble is a metamorphic rock formed under the influence of heat and pressure and consists of a mass of interlocking calcite or dolomite crystals. Pure marble is white, and some other marbles take their common names from their color or mineral impurities. Marble is often used for fine building material or sculpture, thanks to its beautiful appearance.
Marcasite is a polymorph of pyrite. It has the same chemistry, but a different crystal structure. In the jewelry trade, the names pyrite and marcasite are often used interchangeably. Marcasite is often cut and polished in a cone or pyramid shape and pave set between sterling silver beads to enhance their brilliance.
Maw-sit-sit is a rock composed primarily of kosmochlor with varying combinations and amounts of other minerals. Due to its close resemblance to jade, it was believed to be a variety of jade up until the 1960s. This gem is opaque saturated green with dark green to black veining or mottling.
Melo Melo Pearl
The Melo Melo pearl comes from the Melo Melo sea snail, a group of sea snails with scroll-like volute shells found in the South China Sea. The melo pearl is a non-nacreous pearl with colors ranging from light tan to brown, but orange is the most sought-after color. Melo Melo pearls are extremely rare, as no harvesting techniques exist.
Mesolite is a zeolite mineral that occurs in delicate, needle-like crystal structures that radiate from its base. Prized by collectors for its striking crystal formation, mesolite is typically white or colorless, but occasionally light yellow in color. Large specimens are very rare, and faceted gems are almost non-existent.
A meteorite is a solid piece of debris that originated in outer space, entered Earth's atmosphere, and survived impact with the surface. These fragments are usually from comets or asteroids, or debris from the Moon or Mars. There are several known meteorite impact sites, including Campo Del Cielo, Argentina, the Sikhote Alin Mountains in Primorye, Russia, and the Sahara Desert region of Morocco. Meteorites are separated into three types based on their metal content: iron, stony-iron and stony.
Mimetite is a lead-arsenate mineral belonging to the apatite group. It forms a series with vanadinite and pyromorphite. For this reason, the mineral is named for the Greek word for imitator due to its resemblance to pyromorphite.
Synthetic moissanite is an incredibly durable gem. In fact, the ceramic version of synthetic moissanite, called synthetic silicon carbide, is so hard and tough that it is used for body armor and mirrors in orbiting space telescopes! Fortunately, it also makes a gorgeous gem. Synthetic moissanite has a higher dispersion value (fire) than diamond, making it an impressive jewel. Each lab created gem is faceted by a skilled cutter to maximize its brilliance and enhance its exceptional fire. Second in hardness only to diamond, it is extremely resistant to scratching, abrasion, breaking and chipping.
Moldavite is a silica rich tektite found near the Moldau River in Czechia. Moldavite is a natural glass formed as a result of a meteorite impact with the earth. It was first discovered in the late 1700’s in what was then known as western Moravia. The colors of moldavite range from yellowish green to green and brownish green.
Montebrasite is a light green to yellow or colorless gemstone that belongs to the amblygonite group. Similar to amblygonite in chemical composition, it has less fluorine content and twinned crystals are common. Montebrasite was named for its discovery in Montebras, France.
Mookaite comes in the warm earthy colors of reds, yellows, and browns. It is a silica-rich porcelanite (a natural ceramic) created by the weathering of a special rock deposit in Western Australia. It owes its bold colors and texture to its variable composition. In 2011 pink mookaite was discovered at the Binthalya prospect.