Widely used today in stone carving, the Tree agate or Dendritic agate was discovered between the 4th and 3rd century BC along the shoreline of river Achates and named by a Greek philosopher and naturalist, Theophrastus. Carved images discovered in several ancient sites show that this stone was a valuable material for the ancient sculptors. It has been included in the family of quartz, but unlike other minerals in the classification, the Tree agate is not banded. It is called by its name because of the fern-like shapes caused by iron oxides and manganese in them.
Referred to as Moss Agate as well, this mineral is formed under low pressure and temperature by the deposit of late hydrothermal solution close to or at the surface of the earth. The deposit from meteoric groundwater with gelatinous silica can also crystallize into Tree agate in cavities and veins. It has greasy luster and moderate specific gravity ranging around 2.55 to 2.7. It has Mohs hardness of 6 while its cleavage planes are indiscernible. With a refractive index of 1.53 to 1.54, it possesses a microcrystalline Hexagonal-Trigonal system. It generally occurs in a massive form but occasionally may occur as nodular, mammillary, or botrydial form. It has conchoidal or granular fracture while it lacks pleochroism.
The mineral is found in different countries such as USA, Morocco, Czech Republic and India. Tree Agate is a versatile stone as it can be put into many uses. Right from the early years of human history, this stone was used for several purposes. The ancient Babylonians wore it as amulets and used it for decorative purposes. The new world’s decorative artists have continued to use this stone to create a lot of items such as brooches, pins, inkstands, paper knives, seals, and marble. By combining it with other precious stones such as diamond, Faberge, a Russian designer was able to fabricate an awesome piece of value. Mortars and pestles used in chemical laboratories for pounding and mixing chemicals are made from Moss agate thanks to its toughness and resistance against acid and similar chemicals.
As with other minerals of the same class, the Tree agate has been deployed extensively in the industrial and manufacturing sector due to its hardness and its ability to be cut into the desired shape. The stone has gained the reputation of being a stone of abundance in all aspects of life including agriculture and business.
It was a valuable stone for ancient sculptors who used it for stone carving. In the middle ages, many people wore jewelry and other fashion accessories made of agate in order to obtain favor from God. It was also a practice to wear such accessories for protection against dangers, victory against evils and to give way to a good dream. People also wore it as a remedy for insomnia.