Sapphire Deposits: Types, Uses & Mining

Sapphire mines are primarily deposits containing sapphires, which are a type of corundum deposit. The chemical composition of sapphire is aluminum oxide (Al₂O₃), which often appears blue due to small amounts of iron and titanium. In the arc-type grinding, the internal rich and the bottom parallel and oriented arrangement of the three inclusions groups can produce a beautiful six-shot starlight, known as “starlight sapphire”. The gemstone industry will corundum gemstones in addition to ruby, the rest of the various colors such as blue, light blue, green, yellow, gray, colorless, etc., are known as sapphire, or known color sapphire, that is, in front of the sapphire plus the name of the color, such as pink sapphire.

Sapphire Deposits Types

There are mainly the following types of sapphire deposits, which are classified according to their metallogenic environment and the geological characteristics of the ore endowment:

1. Primary deposits

Causes: Primary sapphire deposits are usually formed in magmatic rocks (such as gabbro, and basalt) or metamorphic rocks. They are usually generated in a high-temperature, high-pressure geological environment and are accompanied by aluminum-rich minerals.

Typical characteristics: The ore is mined directly from the parent rock and usually contains unweathered minerals and impurities.

Typical areas: Australia, New Zealand, and parts of Thailand. These deposits are often rich in sapphires of various colors, blue, green, yellow, and pink.

2. Alluvial deposits (secondary deposits)

Causes: Alluvial deposits are deposits where sapphires from the host rock are deposited in rivers, sand dunes, or lake beds through weathering, erosion, and transportation processes. The sapphires are separated and deposited during the transportation process, forming areas of highly concentrated ore.

Typical characteristics: high purity of the ore, large grain size of the ore, and usually easy to mine. The sapphires in the deposits tend to be rounded and gravelly.

Typical areas: Sri Lanka, Madagascar Myanmar, etc. Sapphires from these areas usually form older gemstone deposits due to water transport.

3. Vein deposits

Causes: Vein deposits are formed deep in the earth’s crust, where high-temperature minerals brought in by hydrothermal activity are deposited in rock fissures, fault zones, or volcanic channels. Sapphires crystallize under high pressure and temperature and are gradually deposited in veins.

Typical characteristics: the ore is mainly distributed along fissures and faults in the rock, and the sapphire grains are relatively small but of high grade.

Typical areas: Mogok in Myanmar is a famous source of vein-type sapphires, and these deposits are often accompanied by rubies and other corundum minerals.

4. Sedimentary deposits

Causes: Sedimentary deposits are formed when sapphires are transported and deposited in lakes, coasts, and river deposits. Sapphires in sedimentary deposits usually come from redepositional processes of erosion and weathering.

Typical characteristics: The ore is relatively pure and easy to mine, but due to the dispersed nature of the ore in the sediments, extensive washing and screening are often required.

Typical areas: Sri Lanka and Madagascar sapphire deposits are dominated by this type, and sapphires are mostly distributed in the form of alluvial ores.

5. Volcanic deposits

Causes: The sapphire of this type of deposit is formed during a volcanic eruption and cooling process. Volcanic eruptions bring sapphire minerals to the surface, usually accompanied by basalt and other magnesium- and aluminum-rich volcanic rocks.

Typical characteristics: Sapphires are found in volcanic eruption deposits with complex associated minerals, sometimes containing high-temperature minerals such as magnetite.

Typical areas: Volcanic sapphire deposits dominated by basalt in areas such as Queensland, Australia.

These deposit types determine the distribution characteristics, color, and quality of sapphires, as well as affect how they are mined and processed. The different deposit types also have specific requirements for the extraction and washing processes of the ore.

Sapphire Deposits Uses/Application

Sapphire ore has a wide range of uses, mainly used in jewelry, industry, high-tech fields, and so on. The following are the main uses of sapphire ore:

1. Jewelry

Gemstone use: Sapphire has become an important gemstone material due to its rich color (including blue, pink, yellow, etc.) and high hardness (9 on the Mohs hardness scale). Cut and polished sapphires are widely used to make rings, necklaces, bracelets, and other high-grade jewelry.

Symbol of remembrance: Sapphire is believed to symbolize loyalty and wisdom, widely used in wedding rings and anniversary jewelry, loved by consumers worldwide.

2. Precision instruments and high-tech products

Optical lenses: Sapphire’s high transparency, high-temperature resistance, and high hardness are widely used in the manufacture of precision optical lenses and windows, such as laser lenses, windows of astronomical observation instruments, and components of high-precision imaging equipment.

Electronic devices: Sapphire glass, with a hardness second only to diamond and excellent abrasion resistance, is widely used for the screen and surface glass of smartphones and high-end watches. In addition, sapphire substrates are commonly used in LED lighting equipment and other semiconductor fields.

3. High-temperature and corrosion-resistant materials

Industrial parts: Sapphire material has excellent corrosion resistance and high-temperature resistance, so it is often used in aerospace, oil exploration, and other fields to manufacture wear-resistant and high-temperature-resistant parts.

Chemical equipment: due to sapphire’s resistance to acid and alkali corrosion, some chemical equipment and pipeline lining will use sapphire materials to extend equipment life.

4. Medical and scientific experiments

Surgical equipment: Sapphire is used to manufacture some precision medical instruments and surgical blades due to its high hardness, good wear resistance, and biocompatibility.

Scientific research: In scientific research, sapphire crystals are often used to make detector windows and protective layers for high-temperature experimental equipment to ensure a stable observation environment.

5. Laser and Optoelectronics

Laser equipment: Sapphire is able to withstand high-energy laser emission and is therefore widely used as a window material for lasers. Doped titanium sapphire is also used as a laser gain medium in tunable lasers with a wide wavelength range.

Optical semiconductor substrate: Sapphire substrate has become a commonly used material for LED chip manufacturing due to its stable crystal structure and good insulating properties, which has greatly promoted the development of lighting and display technologies.

6. Collecting and investment

Some rare color or high-purity sapphires have collection value due to their scarcity and uniqueness and have become a popular gemstone species for investment. High-quality natural sapphire ores or cut and processed sapphires are often used as collectibles or auction items.

In summary, in addition to being used as gemstones for jewelry manufacturing, sapphires are also widely used in high-tech fields. For example, because of its high hardness, high-temperature resistance, and corrosion resistance, sapphire material is used in high-tech products such as precision instruments, watch face glass, cell phone screens, and laser windows.

Sapphire Ore Mining

Sapphire ore is usually obtained through open-pit mining and underground mining. Since sapphires are generally found as primary or secondary alluvial ores, the ore is usually sorted, washed, and graded to obtain high-quality stones. If you are looking for a sapphire washing plant solution, please contact us.