Results for “null”

Cubic Zirconia (abbreviated CZ) is the best-known man-made diamond simulant. A simulant is any material, natural or created by man, which imitates the appearance of a natural gem whereas a synthetic gem is man-made but must have a natural counterpart that duplicates the chemical, optical, and physical properties of the natural gem. While it's often touted as the most popular diamond simulant, cubic zirconia is also a synthetic gem. Natural crystals of cubic zirconia have only been found as inclusions in zircon.

While most members of the beryl family such as emerald or aquamarine are famous for their colors, goshenite is the highly collectible colorless variety that displays a diamond-like fiery brilliance. Interestingly, pure beryl is colorless, with traces of different metallic elements being responsible for this gem family's great color range. Always limited in availability, goshenite is named for the locale where it was first discovered--Goshen, Massachusetts.

A plentiful, affordable, and colorful gem, many consider fluorite one of the most popular collector's stones worldwide. Fluorite often has excellent clarity and crosses the entire color spectrum. One of the most famous fluorescent minerals, fluorite often requires no type of treatment to enhance its appearance. Also prized for its color-change and distinctive multi-color banded varieties, this beautiful stone has so many appealing features, it's no wonder that Roman historian Pliny the Elder named fluorite his "most precious substance."

Citrine is one of the most popular gemstones in the quartz group. Prized for its excellent transparency, citrine is one of November's birthstones. Naturally, it occurs in close proximity to amethyst and is found in beautiful golden, mandarin orange and madeira red hues. It's possible that quartz crystals that grew naturally as amethyst or smoky quartz were turned into citrine by natural heat from nearby magma activity. Today, many of the citrines on the market are actually heated amethyst or smoky quartz.

Ammonites were marine animals that existed during the Jurassic and Cretaceous periods, and are related to modern-day octopi, squid and cuttlefish. The same event that wiped out dinosaurs was the end of this species, as well. On rare occasions, the ammonite fossilized shells became mineralized, exhibiting a striking iridescent play of color. Ammonite is typically found as fossil specimens or as iridescent gems cut from the fossils under the trade name Ammolite.

Topazolite is an Andradite Garnet that is yellow or brownish in color. It has a similar appearance to Topaz, and this resemblance inspired its name.

Anglesite gets its name from a deposit locality: Anglesey, an island in Wales. Anglesite forms several types of crystal habits: tabular, prismatic, pseudorhombohedral, or pyramidal. They resemble those of barite and celestite. Prized by collectors for its strong dispersion, anglesite is often colorless to white, grayish, yellow, green or blue.

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.

Preseli Bluestone is found in the Preseli Hills located in Pembrokeshire in western Wales. Preseli Bluestone is spotted Dolerite which is a type of igneous rock that contains spots or clusters of plagioclase feldspar that make each distinctively different from the next. It is a medium-grained, heavy rock that is harder than granite. Preseli Bluestone was used in the construction of the inner rock circle at Stonehenge. It is widely believed these multi-ton stones were carried nearly 200 miles from the Preseli Hills in Wales to Stonehenge around 2300BC during the third phase of its construction and aligned to the summer solstice. Perseli bluestone tools, such as axes, that were made by ancient civilizations have been found all over the British Isles.

Willemite was discovered in 1830 and named after William I, King of the Netherlands. This stone has remarkable luminescent properties. Some specimens glow under an ultraviolet source and continue to glow after the UV light has been removed, a phenomenon called phosphorescence. Specimens that are faceted make beautiful gemstones in blue, yellow, green and brown colors.

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.

Known for its lively, flaming color displays, boulder opal is in high demand by collectors and jewelry designers. As opposed to cut opal gems, boulder opal features small opal veins running through its matrix. The precious opal's rainbow of colors make a dramatic contrast to the rich earthy reds and browns of the host rock, creating a one-of-a-kind display.