When we think of exceptional minerals and rocks, we usually think of diamonds. Although they may be a girl’s best friend (and a spouse’s financial nightmare), there are many excellent alternatives.
Rocks and mineral formations can have some truly amazing shapes and colours. From looking almost alien (see #10) to obscure, nearly all feature vibrant colours. It’s important to note the difference between rocks and minerals. Minerals naturally form and are represented by a chemical formula (e.g. Fluorite is a form of calcium fluoride, CaF2), but rocks feature various compounds and cannot. It’s also possible to artificially dye formations. Nonetheless, we’ve listed 10 of our favourites below.
Which do you prefer?
Fluorite is composed of calcium and fluorine and in is use in a wide variety of chemical and ceramic processes. Specimens with exceptional transparency and colour are cut into gems or used to make ornamental objects.
#2. Chrysocolla in Malachite (Gem Silica)
Chrysocolla, also known as gem silica, is a bluish-green to greenish-blue variety of quartz that receives its vivid colour from the presence of copper. It is often known as “chrysocolla chalcedony” or “gem silica chrysocolla.”
Gem silica is the most valuable variety of chalcedony, with quality cut gemstones selling for over $100 per carat. The best specimens have a pleasing blue colour with strong saturation, a uniform translucence, and and a lack of inclusions.
#3. Sunset Fire Opal
“Fire Opal” is a term used for colourful, transparent to translucent opal with a background colour that is a fire-like hue of yellow to orange to red.
The value of a fire opal is based upon the desirability and uniformity of its colour, with yellow being on the low end of value and red being on the high end.
Bismuth, which has been known since ancient times, was often confused with lead and tin. Bismuth was first shown to be a distinct element in 1753 by Claude Geoffroy the Younger. It’s also an ingredient in Pepto-Bismol!
Alexandrite is the colour-change variety of chrysoberyl. The most striking specimens have a green to blue-green colour in daylight but change to a red to purplish-red colour under certain light. It’s a highly desirable stone and sells at very high prices, especially with stones over five carats being especially rare.
Obsidian is usually an extrusive rock – one that solidifies above Earth’s surface. However, it can form in a variety of cooling environments including along the edge of lava flow!
With its beautiful deep orange-red colour, Crocoite is a mineral that fascinates collectors. It was first found in Russia and later in other countries around Europe, but only sparingly and in very small crystals.
The Australian discovery on the island of Tasmania took this mineral to a whole new level when large, brilliant, well-formed crystals larger and more abundant than any other localities were found.
Uvarovite is consistently deep green in colour. It was first discovered in 1832 by Germain Henri Hess, who named the new mineral after Count Sergei Semenovitch Uvarov (1765-1855), a Russian statesman and mineral collector.
Superman had better stay clear, just in case.
Rhodochrosite is a very desirable mineral generally found in clusters of deep red and hot pink crystals and is highly sought after. Some of the largest and most fascinating specimens have come from Sweet Home Mine in Colorado, U.S. The largest Rhodochrosite crystal, called the “Alma King”, is a single 15 cm crystal that was found in the Sweet Home Mine in 1992.
#10. Galaxy Luz Opal
The Galazy Luz Opal is the largest polished opal in the world, certified by the Guinness Book of World Records in 1992. It was discovered in the Boi Morto Mine in Brazil in 1976 and is part of a private collection. At 3,749 carats, it’s roughly the size of a grapefruit.