Hessonite or Cinnamon Stone is a variety of grossular

Grossular

Grossular or grossularite is a calcium-aluminium mineral species of the garnet group with the formula Ca3Al23, though the calcium may in part be replaced by ferrous iron and the aluminium by ferric iron. The name grossular is derived from the botanical name for the gooseberry, grossularia, in...

, a calcium aluminium mineral of the garnet

Garnet

The garnet group includes a group of minerals that have been used since the Bronze Age as gemstones and abrasives. The name "garnet" may come from either the Middle English word gernet meaning 'dark red', or the Latin granatus , possibly a reference to the Punica granatum , a plant with red seeds...

 group with the general formula

Formula

In mathematics, a formula is an entity constructed using the symbols and formation rules of a given logical language....

 Ca₃Al₂Si₃O₁₂. The name is from the Greek

Greek language

Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...

 hēssōn, inferior, in allusion to its lower hardness and density than most other garnet species varieties.

It has a characteristic red color, inclining to orange, much like that of gem zircon

Zircon

Zircon is a mineral belonging to the group of nesosilicates. Its chemical name is zirconium silicate and its corresponding chemical formula is ZrSiO4. A common empirical formula showing some of the range of substitution in zircon is 1–x4x–y...

. Indeed it was shown many years ago, by Sir A. H. Church, that many gems

Gemstone

A gemstone or gem is a piece of mineral, which, in cut and polished form, is used to make jewelry or other adornments...

, especially engraved gemstones, commonly regarded as zircon, were really hessonite. The difference is readily detected by the specific gravity, that of hessonite being 3.64 to 3.69, whilst that of zircon is about 4.6. Hessonite has a similar hardness to that of quartz

Quartz

Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...

, about 7 on the mohs

Mohs scale of mineral hardness

The Mohs scale of mineral hardness characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer material. It was created in 1812 by the German geologist and mineralogist Friedrich Mohs and is one of several definitions of hardness in...

 scale, whilst the hardness of most garnet species can reach 7.5.

Hessonite comes chiefly from ri Lanka]and India where it is found generally in placer

Placer mining

Placer mining is the mining of alluvial deposits for minerals. This may be done by open-pit or by various surface excavating equipment or tunneling equipment....

 deposits, though its occurrence in its native matrix is not unknown. It is also found in Brazil

Brazil

Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

 and California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

.

Hessonite is also called Gomedhaka in Tamil and Sinhalese.