Herman Hiss & Company

Garnet (January): Garnet is a group of minerals that have been used since the Bronze Age as gemstones and abrasives. Garnets are most often seen in red, but are available in a wide variety of colors spanning the entire spectrum. The name "garnet" comes from the Latin granatus ('grain'), possibly a reference to the Punica granatum ('pomegranate'), a plant with red seeds similar in shape, size, and color to some garnet crystals.

Amethyst (February): Amethyst is a violet or purple variety of quartz often used as an ornament. The name comes from the Greek a ('not') and methuskein ('to intoxicate'), a reference to the belief that the stone protected its owner from drunkenness; the ancient Greeks and Romans wore amethyst and made drinking vessels of it in the belief that it would prevent intoxication.

Aquamarine (March): Aquamarine (Lat. aqua marina, "water of the sea") is a gemstone-quality transparent variety of beryl, having a delicate blue or turquoise color, suggestive of the tint of seawater. It's closely related to the gem emerald. Colors vary and yellow beryl (heliodor), rose pink beryl (morganite), and white beryl (goshenite) are known.

Diamond (April): Diamond is the allotrope of carbon where the carbon atoms are arranged in an isometric-hexoctahedral crystal lattice. Its hardness and high dispersion of light make it useful for industrial applications and jewelry. It is the hardest known natural material and the third-hardest known material after aggregated diamond nanorods and ultrahard fullerite.

Emerald (May): Emeralds are variety of the mineral beryl, colored green by trace amounts of chromium and sometimes vanadium.[1]. Beryl has a hardness of 7.5-8 on the 10 point Mohs scale of mineral hardness.[2] Most emeralds are highly included, so their brittleness (resistance to breakage) is classified as generally poor. The origin of the word 'emerald' is said to be a Sanskrit word meaning 'green'.

Pearl (June): A cultured pearl is a pearl created by a pearl farmer under controlled conditions. A pearl is formed when some sort of small object, typically a parasite or piece of organic matter, becomes embedded in the tissue of an oyster or mollusk. In response, the mantle tissue of the mollusk secretes nacre, a combination of crystalline and organic substances. As the nacre builds up in layers, it surrounds the irritant and eventually forms a pearl.

Ruby (July): Ruby is a pink to blood red gemstone, a veriety of the mineral corundum (aluminium oxide). The common red color is caused mainly by the element chromium. Its name comes from ruber, Latin for red. Other varieties of gem-quality corundum are called sapphires. It is considered one of the four precious stones, together with the sapphire, the emerald, and the diamond. Improvements used include color alteration, improving transparency by dissolving rutile inclusions, healing of fractures (cracks) or even completely filling them.

Peridot (August): Peridot is the gem quality variety of forsteritic olivine. The chemical composition of peridot is (Mg, Fe)2SiO4, with Mg in greater quantities than Fe. The name of the gemstone is believed to come from either the Arabic word faridat meaning 'gem' or the French word peritot meaning 'unclear.' Peridot is one of the few gemstones that comes in only one color. The depth of green depends on how much iron is contained in the crustals structure, and varies frmo yellow-green to olive to brownish green. Peridot is also often referred to as 'poor man's emerald'. Olivine is a very abundant mineral, but gem-quality peridot is rather rare. Peridot crystals have been collected frmo iron-nicket meteorites.

Sapphire (September): Sapphire refers to gem varieties of the mineral corundum, an aluminium oxide (Al2O3), when it is a color other than red. Sapphire can be found naturally or manufactured in large crystal boules. Because of its remarkable hardness sapphire is used in many applications, including infrared optical components, watch crystals, high-durability windows, and wafers for the deposition of semiconductors, suchs as GaN nanorods.

Opal (October): Opal is amorphous SiO2-nH2O, hydrated silicon dioxide. The water content is usually between three and ten percent, but can be as high as 20%. Opal ranges from clear through white, gray, red, orange, yellow, green, shore, blue, magenta, rose, pink, slate, olive, brown, and black. Of these hues, the reds against black are the most rare and dear, whereas white and greens are the most common; these are a function of growth size into the red and infrared wavelengths-see precious opal. Common opal is truly amorphous but precious opal does have a structural element. The word opal comes from the Latin opalus, by Greek opallios, and is from the same root as Sanskrit upala[s] for "stone", originally a millstone with upara[s] for slab. Opals are also Australia's national gemstone.

Citrine (November): Citrine, also called citrine fortz is a variety of quartz. It ranges in color from a pale yellow to brown. Citrine has ferric impurities, and is rarely found naturally. Most commercial citrine is in fact artificially heated amethyst or smoky quartz. Brazil is the leading producer of naturally mined citrine, with much of its production coming from the state of Rio Grande do Sul.

Turquoise (December): Tranzanite is the blue/purple variety of the mineral zoisite discovered in the Meralani (Merelani) Hills (Merelani) of northern Tanzania in 1967, near the city of Arusha. It is a popular and valuable gemstone when cut, although its durablility is somewhat lacking; its tendency to break sometimes precludes appropriate use as a ring stone. Tanzanite is noted for its remarkably strong trichroism, appearing alternately sapphire blue, violet, and sage-green depending on crystal orientation. However most tanzanite is subjected to artificial hear treatment to improve its colour, and this significantly subdues its trichroism.