The solid and hard masses that make up the earth's crust are called rock or stone. Mainly, these stones are formed by the combination of more than one mineral. Stones are the best known building materials used throughout history to protect people. Stone has always been used in arches, walls, windows, flooring and roofing.

Despite the developing technologies and knowledge, natural stones have always gained an important place in human life. In this respect, our country is in a lucky position in terms of the presence of natural stone. Both in terms of reserves and diversity, the potential in our country is enormous. Our country is one of the richest countries especially in terms of marble. With more than one billion cubic meters of marble reserves, our country has nearly half of the world's marble reserves. There are more merme varieties than 5 in different designs and colors. Our country ranks seventh in the world natural stone production.

However, not only marble but also granite, syenite, basalt, andesite, limestone and travertine are included in the scope of natural stone.

Various studies are carried out in our country in order to determine the location of natural stones used as building materials, to determine their properties and to examine their geographical distribution.

Some of the stones are metamorphic, some are sedimentary and some are magmatic. For example, marbles have metamorphic properties, while travertine and onyxes have sedimentary features. Granites and basalts have magmatic properties.

40 percent of natural stones, mainly marble, is used in flooring, 27 percent is used in interior and exterior cladding works, and 13 percent is used in monuments and cemeteries. Anthers, stair steps, kitchens, baths, bathroom sinks and worktops, fireplaces are natural stone (marble) usage areas. Marble is a building material that can be used in a wide area from very small ornaments to the covering of very large areas.

Natural stone tests are performed in authorized test and inspection laboratories. During these tests, the current regulations and published standards are taken into consideration. A number of standards based on natural stone tests are:

• TS 10449 Marble - Calcium carbonate based - Used as building and covering stone
• TS 11443 Onyx marble - Calcium carbonate based - Used as building and covering stone
• TS EN 1467 Natural stones - Raw blocks - Specifications
• TS EN 12407 Natural stones - Test methods - Petrographical investigation
• TS EN 13373 Natural stones - Test methods - Determination of geometric properties of units
• TS EN 13919 Natural stones - Test methods - Determination of resistance to so2 degradation in humid environment
• TS EN 14158 Natural stones - Test methods - Determination of breaking energy
• TS EN 14581 Natural stones - Test methods - Determination of linear thermal expansion coefficient
• TS EN 15163 Machines and installations for extraction and processing of natural stones - Safety - Rules for diamond wire cutting machines
• TSE CEN / TR 17024 Natural stones - Guide to the use of natural stones