What is Ruby Mining ?

Ruby mining involves the extraction of rubies, which are precious gemstones known for their red color. Rubies are a variety of the mineral corundum, and their red hue is due to the presence of chromium. The process of mining rubies can vary depending on the geological characteristics of the deposits.

Process of Ruby Mining

The process of ruby mining involves several steps, from exploration to the extraction and processing of the gemstones. Here's a more detailed overview of the typical process:

• Exploration:

Geological surveys and exploration are conducted to identify potential ruby deposits.Geologists look for indicator minerals and study the geological formations to determine the likelihood of finding rubies.

• Site Preparation:

InOnce a potential deposit is identified, the site is prepared for mining.This may involve clearing vegetation and removing any surface materials to access the underlying rocks.

• Open-Pit Mining:

For deposits near the surface, open-pit mining is often employed. Overburden (rock and soil covering the ruby-bearing rocks) is removed to expose the gem-bearing rocks below.

• Underground Amber Mining:

In some cases, rubies may be found in deeper formations, requiring the creation of tunnels or shafts for extraction.

• Extraction of Ruby:

Ruby-bearing rocks are extracted from the pit or underground workings.The extracted material is transported to the processing plant.

• Sorting and Processing:

The extracted material goes through a sorting and processing phase to separate rubies from the surrounding rocks and minerals.Techniques such as washing, screening, andhand-sorting may be used to isolate the rubies.

• Cutting and Polishing:

Rough rubies undergo cutting and polishing to enhance their brilliance and appearance. Skilled gem cutters shape the raw crystals into faceted gems, bringing out the vibrant red color.

• Grading:

The finished rubies are graded based on factors such as color, clarity, cut, and carat weight.Gemological institutions like the Gemological Institute of America (GIA) provide standards for ruby grading.

• Market Distribution:

The graded and processed rubies are distributed to the market through various channels, including gem dealers, jewelry manufacturers, and retailers.

Treatment of Ruby Mining

Very few samples of corundum have a natural color within the range required for a ruby. Also very few have the clarity required to produce a nice cut stone. Long ago, people who prepare gem materials for cutting began experimenting with ways to improve their color and clarity.

Heating

Heating ruby crystals under controlled conditions can improve or intensify their color. Heating can also remove inclusions by causing them to dissolve, making them less visible and improving the clarity of a gem. Today, most of the rubies in the market have been heated to improve their color and clarity. This heat treatment is normal and expected in the gem trade, but a seller should disclose the treatment to a buyer in advance of a sale.

Fracture Filling

One of the ancient treatments was to fill surface-reaching fractures with oils, waxes, or resins. These treatments filled pits and fractures on the surface of the gem and improved their appearance. However, these treatments are not permanent because the oils can be washed out, and the waxes and resins can crack and fall out with age. They produce a temporary improvement in the appearance of the stone. A more permanent type of fracture treatment is to fill the fractures with minor amounts of flux, glass, or another durable material. These enter the fractures during the heat treatment process.

When the stone cools, a permanent filling of the fracture was accomplished. These treatments reduce the visibility of the fractures and improve the clarity of the gems and might also improve the durability of some stones. A much more aggressive treatment is to heat the gem to a very high temperature and inject glass or flux into the fractures. The temperature of this treatment can be high enough that some of the ruby melts and mixes with the fracture-filling materials. The result of this treatment is an altered stone with an improved quality and appearance. But the stone now contains an unknown and possibly significant amount of non-ruby material.

Composition and Formation

Rubies are made up of the mineral corundum. Corundum is aluminum oxide (Al2O3). A ruby is formed when there is a small impurity of chromic oxide in the corundum. This substitution process is called an isomorphous replacement. Chromium and vanadium, another metal constituent of rubies, provide the blazing red color of the crystal. Ruby crystals form at high temperatures, between 620°C and 670°C. They appear to be the features of hydrothermal reactions with marble.

They are formed mainly in high-grade metamorphic environments where hydrothermal fluids meet limestones. Rubies can also be created in a laboratory, using two different methods: Flame-Fusion and Flux-Growth. The cheapest method of producing synthetic rubies is the flame-fusion process. The chemicals are melted and dripped onto a bowl. The melt then crystallizes within a matter of hours. The result is an unnatural, glassy stone with curved growth plates. Instead of inclusions, flame-fusion rubies have tiny gas bubbles. They cost $1-4 per carat. Such a ruby is often used in costume jewelry.

World Wide Ruby Mining

Most gem-grade corundum forms in metamorphic rocks or in igneous rocks. Mining small gems from hard rock is possible, but it is very expensive, and many of the gems are broken during the mining process. Fortunately, corundum is very hard and resistant to weathering. Rubies occur in corundums. Today, the gems are mined from the stream sediments. Their high specific gravity relative to other sediment particles often causes currents to concentrate them in small placer deposits. Most of the rubies are produced by washing the gravels of these stream deposits. This work is often done by hand because the deposits are small and irregular in shape and character. These deposits are often located in countries where wages are very low and mining is prevalent.

Burma(Myanmar)

Corundum has been found in a number of different areas of Burma. These include Sagyin, Thabeitkyin, Naniazeik, Mogok and, most recently, Mong Hsu. Most famous is the Mogok Stone Tract, which has remained the world's premier source of ruby for more than 800 years.

India

The Karur-Kangayam and Hole-Narsipur belts, in the southern Indian states of Tamil Nadu and Karnataka, respectively, are famous throughout the subcontinent for their gemstones. The city of Karur is well known for rubies. Ruby is also found in Subramania near Madikeri in Karnataka. Channapatna, roughly 280 km from Madikeri, is famous for its star rubies. In all of these locations, mining is performed using primitive methods. Good-quality transparent rubies come from the Karur region, though color varies along this gemstone belt.

The mines situated in Karur are located on barren land along the roadside; the nearby towns of Kangayam and Paramatti also have ruby mines. In the town of Subramaniam, close to Madikeri, large hexagonal pillars of ruby are mined; deposits are also located in the nearby villages. The stones are mainly hexagonal but come in many sizes and shapes. They have a maroon color. These rubies range from 20 to 100 mm, with the length across the prism faces varying from 10 to 50 mm. In the Bangalore district of Karnataka, opaque maroon star ruby is found in the village of Channapatna and other nearby villages. In certain areas such as Sengal and Kiranur, rubies are found in association with gem-quality iolite (cordierite). Madikeri ruby have a mineral assemblage of mica, quartz, corundum.

Prominent Ruby Deposits

The most quality ruby deposits are found in Central and South-East Asia. The Mogok deposit in Myanmar produces the highest quality rubies, reputed for their intense "pigeon blood" color and their transparency. Rubies are mined in Myanmar using five different methods. A ruby larger than 10 carats is worth more than an equivalently sized diamond, because it is so rare. The center of Ruby gemstone trade is in Bangkok, Thailand. The Chantaburi Province in Thailand has always been an important source of Rubies, producing gems with excellent clarity but with less desirable browner tones.

There are strict trade embargoes and restrictions again Burma for its human rights violations, and several countries, especially the United States, ban any exports from this county. In 2000, new Ruby sources were discovered in Madagascar. These deposits turned out to be very extensive and productive, and Madagascar is now one of the leaders in Ruby output. Other important Ruby sources include Sri Lanka, India, Cambodia, Vietnam, Tanzania, and Mozambique. Other sources of Ruby include Afghanistan, Pakistan, Tajikistan, Australia, and the U.S. (North Carolina).

Varieties of Ruby

Burma Ruby - Ruby from Burma; synonym of Burmese Ruby.

Burmese Ruby - Ruby with an exceptional red color (usually but not necessarily from Burma). Occasionally also used to describe synthetic Ruby.

Pigeon's Blood Ruby - Highly-desirable form of Ruby of a blood-red color with a hint of blue.

Ruby Fuschite - Describes a dark red Ruby in a green Fuschite mica matrix found in India.

Ruby Zoisite - Mixture of opaque red Ruby in green Zoisite from Tanzania. Ruby Zoisite has pretty contrast and is used as a minor gemstone, being polished into cabochons and carved into ornamental figures.

Star Ruby - Well-known form of Ruby displaying asterism, most often in the form of a six-rayed star.

Uses of Ruby Mining

The primary use of ruby mining is to extract rubies, which are precious gemstones valued for their vibrant red color. Rubies have been treasured for centuries and are used for various purposes, including:

Jewelry: Rubies are highly sought after for jewelry, including rings, necklaces, earrings, and bracelets. They are often used as center stones in engagement rings or as accent stones in various pieces of fine jewelry.

Collector's Items: Exceptionally rare and high-quality rubies are sought by collectors and investors. Collectors value rubies based on factors such as color, clarity, size, and overall quality. Astrology and Gemstone

Therapy: In some cultures, rubies are associated with astrological beliefs, and individuals may wear them as gemstone remedies for astrological benefits. Some people believe that wearing or owning a ruby can bring good luck, protection, and positive energy.

Cultural and Religious Significance: Rubies hold cultural and religious significance in various societies.They may be used in religious artifacts, traditional ceremonies, and as symbols of wealth and power.