Almandine is a mineral that is part of the group of garnets and therefore mineralogically it is part of the minerals of the class of nesosilicates. Almandine garnet is characterized by occurring in brown, reddish, and reddish-brown colors.
It is a mineral with a high resistance, which is why it is used in the jewelry and costume jewelry industry, that is to say, this mineral is considered a precious stone. In fact, almandine garnet is the variety of garnet that is most used as a gemstone of all other varieties and is also the type of Garnet most abundant in nature.
Properties and characteristics of the almandine mineral
Color and composition
Almandine garnet is a silicate mineral with iron and aluminum that is considered as a rock-forming mineral. Sometimes iron is partially replaced with magnesium and manganese in igneous rocks.
Due to its composition, the almandine crystal usually has a brown, reddish brown and reddish brown color, very similar to red wine.
| almandine | Physical and chemical properties |
|---|---|
| Chemical formula | Fe3Al2Si3O12 |
| class, group | Silicates, Nesosilicates, Garnet Group |
| Composition | Iron aluminum silicate. Iron is sometimes partially replaced with magnesium and manganese. |
| variable formula | (Fe,Mg,Mn)3Al2Si3O12 |
| Color | Dark red, reddish brown, black. May also be multicolored black with reddish edges or tinges. Rarely pink or purple. |
| Streak | Colorless |
| Hardness | 7.5 – 8.5 |
| crystal system | isometric |
| Transparency | transparent to opaque |
| specific gravity | 4.3 |
| Gloss | Vitreous |
| cleavage | None |
| Fracture | conchoidal unequal |
| Tenacity | Fragile |
| Other identification marks | Paramagnetic (becomes magnetic when heated). |
Crystal shapes
Almandine garnets generally appear as well-formed rhombohedral and trapezoidal crystals, many times appearing combined in these two forms in the same crystal.
Likewise, mineral crystals can appear with striations or staggered layers of crystals.
They can also appear as dodecahedral, grainy, massive crystals and as rounded crystals worn by water.
Due to their formation environment, it can happen that these crystals occur deformed and sub rounded in a micaceous matrix, in the form of a snowball.
Almandine stone meaning
It is believed that the almandine stone directly represents the vital energy of the body and the environment. Thus, it is believed that this crystal manages to activate the vitality of people and is also used for personal motivation and passion for what is done.
In other Eastern cultures they have said that the almandine stone is considered as the stone of tangible truth, therefore its energy is believed to help alleviate fear and worry. It is also said to be an excellent talisman of protection and unbreakable strength.
Origin, formation and deposits of almandine
The mineral almandine is a rock-forming mineral that can occur in both igneous rocks and metamorphic rocks. When it appears in igneous rocks it is due to the direct crystallization of magma and it appears conforming to diorites and granite pegmatites.
When it appears in metamorphic rocks, it forms due to regional metamorphism and forms micaceous schists and gneiss, in addition, it can appear in contact metamorphic rocks such as hornfels.
This gem-quality mineral can be found throughout the world, however we singled out the Brazilian and African cratons for large almandine stones.
Uses of the almandine stone
In jewelry and as a precious stone
The almandine stone as a gem is characterized by being translucent and with well-formed mineral faces. In addition, jewelers consider that it must have a size greater than 5 millimeters to create excellent and valuable jewelry accessories.
When the gem meets quality standards, it is used to create high-quality rings, earrings, pendants or necklaces. This mineral is in fact considered the most abundant gemstone in the garnet group.
As a collection stone
Not all almandine crystals reach gem quality, many of them have uneven faces and are not translucent. However, they usually appear in large sizes and associated with other interesting minerals, especially in pegmatites.
These stones that contain these crystals are highly coveted by mineral collectors.
as abrasive material
Finally, almandine can be used as an abrasive material in the industry that manufactures polishing materials and sharp materials. Almandine is a hard, strong material used to polish steel and other metals to a sharp edge.