Natural Stone Quarrying

In nature, there are valuable stones quarry of all kinds, that man has invented many methods to use these quarries. Mining is called extracting valuable minerals that are naturally located in seams or cracks in mountains, underground, rocks and plaques. The extracted minerals can include all kinds of stones needed by humans, such as metals, coal, sand, precious stones, limestone, gypsum, rock salt, potash, sand and clay.

Some Common Terms In Natural Stones:

Large Blocks(Loafs):

A stone piece that is usually more than several tons and reaches up to 20 tons. The minimum loafs weight depends on the market and the stone type. For example, in the marble case, about 500 kg pieces are also called coupes.

Mill Blocks:

natural stone pieces that are almost in a rectangular cube shape are called mill blocks. The box weight the is usually more than 10 tons.

Plaque:

natural stone plates that are prepared in stone-cutting factories from quarries or coupes and are divided into the desired pieces after sanding and polishing.

Waste Rock:

Natural stones that are obtained during the quarries quarrying or kup and usually do not have a special geometric shape and are mainly removed from the quarry as tailings.

Potted Stone:

Carcass stones that can be used to prepare ornamental objects are called potted stones. In marble quarry, stones weighing less than 500 kg are called potted stones.

To Extract Natural Stones By Mechanized Methods, The Desired Stone Must Have The Following Conditions:

• Alteration (decomposition and weathering) has not occurred in the stone.
• There should be no seams and cracks and fine layering.
• No schistosity (thin layering or torq).
• Be able to cut, maintain and polish.
• Have an acceptable difficulty.
• Suitable quarrying conditions should be provided in order to use mechanized methods.
• Have enough storage and be economical.

Effective Factors In Choosing The Optimal Quarrying Method:

• Geological features
• The region Economic infrastructure
• Storage amount
• Methods Combination: it may be more economical and more appropriate to use one or two methods simultaneously in a quarry according to the topography and mineral type and other factors.
• The using tailings possibility: due to the fact that today it is possible to use the tailings produced in quarry if they are of suitable quality to make stone artefacts. For example, in the thermal method, the waste produced is of very low quality and cannot be used.
• National laws and regulations
• The stone quality or rarity
• Economic justification
• Application Type

Stone Quarring Methods:

• Parallel pit mining.
• Quarrying with stone machines (Havaj).
• Hydromechanical quarrying.
• Quarrying with the heat help.
• Mining with steel cutting wire.
• Mining with a diamond wire cutter.
• Quarrying with expanding chemicals.

Quarrying Natural Stones Common Methods In Iran:

In a situation where the natural stone industry in the world has an annual turnover of more than 80 billion dollars, Iran can export about 8 billion dollars every year by taking a 10% share of this market.

 In Iran, before 1366, most of the miners did not pay special attention to the quarrying method and focused only on reducing the cost and increasing the production, and since decorative stone quarry had good profits, many investors invested in this sector. They were recruited from the quarry, without having any special experience.

In 1366, the Decorative Stones Coordinating Council revolutionized the quarrying method in decorative stone quarry from explosive to new methods in its work program, and in the second mining symposium in Kerman, it made the new quarry exploitation subject to the quarrying methods use without mineral substance.

Currently, 90% of Iran’s decorative stone quarry are extracted with diamond wire. Other quarrying methods that are used either in combination with other methods or according to some quarry special conditions in the country are:

Expansive chemicals (ketrak), manual and mechanical quarrying with the pars and wedges help, hoavage device and steel wire cutters. In some granite quarry or quarry where the thickness of the layers is low, miners use the gaveh and Pars quarrying method, Hauge and Ketrak machines. Although most of the quarry use wire cutters, due to wear and devices tear, lack of principles in the open chest and stairs direction, and standards non-observance, Iran is far from gaining a special position in the natural stones quarrying and this product export.

Sources

• Sharifi, A., (1367), natural stones and their role in the country’s economy, the first seminar papers collection on natural and Tehran Quarry and Metals Ministry decorative stones.
• Iranian stone magazine, autumn and winter 2004, numbers 287 and 286.
• Hamidi-Anarki, G., (1375), quarrying methods without mineral materials, Geological Organization.
• Atae, M., (1387), construction stones, Shahrood Technology University, 1397