Concentric – Circular ring aggregates around a center
This habit is found in cross-sections from reniform/mamillary habits, and also from elongated stalactites of amethyst (quartz), malachites, rhodocrosite, and others Common examples include: quartz, malachite, rhodocrosite
Columnar – Similar to bladed and radial: Long, slender prisms often with parallel growth
Common examples: calcite, gypsum/selenite
Bladed – Blade-like ends, slender and somewhat flattened
Common examples: quartz, stilbite, kyanite
Acicular – Needle-like, slender and/or tapered
Acicular, in mineralogy, refers to a crystal habit composed of slender, needle-like crystals. Crystals with this habit tend to be fragile. Complete, undamaged acicular specimens are uncommon. The term “acicular” derives from the Late Latin “aciculaR
Oltu stone aka black amber, a kind of jet
Oltu stone (Turkish: Oltu taĆı) is a kind of jet found in the region around Oltu town within Erzurum Province, eastern Turkey. The organic substance is used as semi-precious gemstone in manufacturing jewellery. Location and extraction Oltu stone, s
Wood Opal
Wood opal is a form of petrified wood which has developed an opalescent sheen or, more rarely, where the wood has been completely replaced by opal. Other names for this opalized sheen-like wood are opalized wood and opalized petrified wood. It is often used as a gemstone. References
Petrified Wood
Petrified wood, also known as petrified tree (from Ancient Greek ÏÎÏÏα meaning ‘rock’ or ‘stone’; literally ‘wood turned into stone’), is the name given to a special type of fossilized wood, the fossilized remains of terrestrial vegetation. Petrifac
Tongue stone
According to Renaissance accounts, large, triangular fossil teeth often found embedded in rocky formations were believed to be petrified tongues of dragons and snakes and so were referred to as “tongue stones” or “glossopetrae”. Glossopetrae were commonly thought to b
Toadstone aka bufonite
The toadstone, also known as bufonite (from Latin bufo, “toad”), is a mythical stone or gem that was thought to be found in the head of a toad. It was supposed to be an antidote to poison and in this it is like batrachite, supposedly formed in the heads of frogs. Toadstones we
Shaligram
A shaligram, or shaligrama shila (Devanagari:Â à€¶à€Ÿà€Čà€żà€à„à€°à€Ÿà€ź à€¶à€żà€Čà€ŸÂ ĆÄligrÄma-ĆilÄ), is a particular variety of stone collected from riverbed or banks of the Kali Gandaki, a tributary of the Gandaki River in Nepal, used as a non-anthropomorphic representation of Vis
Madstone
In the folklore of the early United States, a madstone was a special medicinal substance that, when pressed into an animal bite, was believed to prevent rabies by drawing the “poison” out. The Encyclopedia Americana described it as “a vegetable substance or stone”.Â
Adder stone aka hag stone
An adder stone is a type of stone, usually glassy, with a naturally occurring hole through it. Such stones, which usually consist of flint, have been discovered by archaeologists in both Britain and Egypt. Commonly, they are found in Northern Germany at the coasts of the North and Baltic S
Snake stone aka viper stone, snake pearl, black stone, serpent stone and nagamani
A snake-stone, also known as a viper’s stone, snake’s pearl, black stone, serpent-stone, or nagamani is an animal bone or stone used as folk medicine for snake bite in Africa, South America, India and Asia. The early Celtic era European Adder stone is also called a snak
Goa stone
A Goa stone or Lapis de Goa was a man-made bezoar that was considered to have medicinal and talismanic properties. Goa stones were made in Goa, India and exported to apothecaries in Europe from the mid-16th to 18th century. Goa stones were manufactured by Jesuits in the late seventeent