Tourmaline
General Information about Tourmaline
- Tourmaline is a mineral that belongs to the tourmaline group.
- It is a complex borosilicate mineral with a wide range of colors.
- Tourmaline is classified into different species based on its chemical composition.
- It is commonly found in granite and pegmatite rocks.
- Tourmaline is widely used in jewelry due to its beauty and variety of colors.
- Tourmaline is piezoelectric, meaning it can generate an electric charge when subjected to pressure.
- It exhibits strong pleochroism, meaning it can show different colors when viewed from different angles.
- Tourmaline has a hardness of 7 to 7.5 on the Mohs scale, making it suitable for everyday wear.
- It has a high refractive index, giving it excellent brilliance and sparkle.
- Tourmaline can be found in various crystal habits, including prismatic, columnar, and bladed forms.
Types and Colors of Tourmaline
- The most common types of tourmaline are schorl, dravite, elbaite, and uvite.
- Tourmaline can occur in a wide range of colors, including black, brown, green, blue, pink, and watermelon (bi-color).
- Some tourmaline varieties, such as Paraiba tourmaline, are highly valued for their intense blue or green colors.
- Color zoning is common in tourmaline crystals, resulting in bands or sectors of different colors.
- Tourmaline can also exhibit cat's eye and star effects, adding to its desirability.
Geological Occurrence of Tourmaline
- Tourmaline is found in many countries worldwide, including Brazil, Afghanistan, Nigeria, and the United States.
- It is commonly associated with pegmatite veins and granitic rocks.
- Tourmaline can also be found in metamorphic rocks, such as schist and gneiss.
- Gem-quality tourmaline is often found in alluvial deposits, where it has been transported by water.
- Certain geological conditions, such as the presence of boron and lithium, favor the formation of tourmaline.
Uses and Significance of Tourmaline
- Tourmaline is highly valued as a gemstone and is used in various types of jewelry, including rings, earrings, and necklaces.
- It is believed to have metaphysical properties, such as promoting healing, protection, and emotional balance.
- Tourmaline is used in the field of science and technology, particularly in piezoelectric sensors and electronic devices.
- Black tourmaline, also known as schorl, is used for its grounding and protective properties in crystal healing.
- Tourmaline is also used in the creation of artworks, sculptures, and decorative objects.
Other Facts about Tourmaline
- Tourmaline is found in a wide variety of colors, ranging from black to colorless, and various shades in-between.
- The main tourmaline producing countries include Brazil, Afghanistan, Pakistan, Nigeria, and Mozambique.
- Brazil is the largest producer of tourmaline.
- The name "tourmaline" is derived from the Sinhalese word "tōramalli," which means carnelian gemstones.
- Heat treatment can alter the color of tourmaline, especially pink to red stones.
- Tourmalines are difficult to detect for irradiation, making it hard to determine if a stone has been treated.
Tourmaline Data Sources
Reference | URL |
---|---|
Glossary | https://harryandcojewellery.com.au/blogs/glossary/tourmaline |
Wikipedia | http://en.wikipedia.org/wiki/Tourmaline |
Wikidata | https://www.wikidata.org/wiki/Q179911 |
Knowledge Graph | https://www.google.com/search?kgmid=/m/07qrp |