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Hematine is a hematite simulant sometimes called hemalyke, hemalike, or magnetic hematite. It was originally reported to be pressed and sintered iron oxide, but most material currently on the market is a ceramic-like material composed of barium-strontium ferrite. Hematine is highly magnetic, whereas hematite is not.

Prase is a dull green to yellowish green variety of chalcedony, a cryptocrystalline quartz. It is commonly fashioned en cabochon to show off its leek-green color. Prase can be confused with chrysoprase since they are very similar in appearance, but a darker, less saturated color is typically indicative of prase.

Rosalinda is found outside Tambo Colorado, Peru, and was introduced to the market in 2011. The white areas of the stone are made up of marialite which is a variety of scapolite. The pink inclusions are the mineral Piemontite which is a member of the epidote group.

In 1839 American mineralogist Charles Upham Shephard discovered a clear, bright, colorless gemstone in Danbury, Connecticut, and named it danburite after the location. Unfortunately for danburite, it was discovered at a time when colored gemstones were heavily promoted and highly desired. This colorless find, therefore, didn't create much excitement at that time. Danburite, which belongs to a class of minerals known as silicates, remained relatively unknown for years, but is steadily growing in popularity today.

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.

Goldstone is glass that contains myriad of tiny angular crystals of copper. First made in Italy, goldstone forms by reduction of particles of copper oxide within the glass during a process called annealing. Nothing in nature looks quite like glittering goldstone. Made in three distinct colors (blue, green and orange), goldstone is a tough and durable material that can be made in large pieces and fashioned into slices and objects of almost any desired size and configuration.

Pollucite is often found in association with petalite (formally known as castorite). It was named after the twin brothers Pollux and Castor in Greek mythology. It is an important source of cesium. Facet grade material is prized by gemstone collectors and can be found in Afghanistan, Pakistan, Russia, and the United States.

Sapphirine was so named because of its resemblance in color to blue sapphire, even though the two minerals have completely different chemical, optical and physical properties. Sapphirine is very rare, with small gems only faceted for collectors. This gem is know for blue color, but occasionally forms in a red-orange variety.

Aeschynite is an uncommon, rare earth mineral that is seldom cut into a gemstone. Two varieties of aeschynite also contain the elements cesium and thorium which are radioactive. It is not recommended to store this mineral in inhabited areas or to have prolonged exposure to the body.

Gypsum is a mineral that has been utilized since antiquity. This soft mineral represents the second level on the Mohs hardness scale. Cut stones are rare because gypsum has perfect cleavage, and it is too soft to facet. The fine-grained variety known as alabaster is used for carvings and decorative objects. Selenite is the large crystalline variety that is popular with mineral collectors. The fibrous variety is known as satin spar. Gypsum sometimes crystallizes in rosette patterns known as desert roses. Gypsum is probably best known for its use in construction materials like sheetrock, cement, and plaster.

Quartz is the name of a large group of minerals comprised of silicon dioxide. Quartz is the most abundant mineral on the Earth’s surface, and it can be found on all seven continents. It is best known as its gemstone varieties Amethyst, Citrine, and Rock Crystal Quartz. Quartz crystals are distinctive six-sided prisms with six-sided pyramid terminations. Quartz specimens are attractive and sought after as decorative items.

A gem known since ancient times, sunstone is a type of feldspar formed and crystallized in lava flows. Radiating with the power of eternal light, sunstone has been reportedly found in the tombs of Viking sailors who believed it would aid in their journey through both life and the afterlife. A distinguishing feature of sunstone is its metallic schiller, which rolls across the stone's surface. The effect is due to the presence of small plate-like inclusions of minerals such as hematite or native copper. These inclusions interfere with the passage of light, causing it to scatter. If the inclusions are larger and visible to the eye, they create glittery star-like reflections that gemologists refer to as aventurescence.