Saudi Gazette report

MAKKAH — What is the secret of the coolness of the floors of the Grand Mosque in the mataf (circumambulation area around the Holy Kaaba) in Makkah even in searing temperatures?

For anyone who has performed the Umrah or Hajj pilgrimages, they will have probably noticed the coolness under foot when they stepped onto the marble floors of the mataf within the Grand Mosque. Many have debated the reason behind the cool feeling, despite the intense Makkah heat that may reach 50 degrees Celsius in the summer. Some may even think that there are air conditioners under the floor, which is totally incorrect.

The General Presidency for the Affairs of the Two Holy Mosques says that the main reason for the coolness is the type of Thassos marble used in the mataf, which may be the largest surficial marble application in the world.

During his reign, King Khalid ordered the expansion of mataf and its floor was furnished with Thassos marble for the first time in the year 1398 AH. This marble reflects the sun’s rays, and in turn, the heat as well during daytime.

According to the presidency, the characteristic coolness of the floors have been attributed to the quality of the marble used in the Grand Mosque. Saudi Arabia has been importing, for decades, the famous Greek Thassos marble because it reflects light and heat, which no other type of granite and marble does.

Thassos marble is the most white and rare marble in the world and its grain is of small size. It received its name from the Greek island of Thassos in the Aegean Sea, from where it has been extracted since ancient times. The Greeks were among the first peoples to discover marble and to develop its uses throughout the ages.

Thassos marble is distinguished by its crystal white color, and it is one of the purest and most solid natural stones. The thickness of the marble used at the Grand Mosque is five centimeters. It is also distinguished by the fact that it absorbs moisture through minute pores at night, and during the day it excretes what is absorbed at night, which makes the floor always cool even in high temperatures.

The material has been described as heat-dissipating smart marble where its high whiteness and purity have been attributed to the stone’s dolomite-rich crystal formation. Its 2mm crystal sheet configuration was then linked with two important factors — minimal porosity and increased thermal conductivity — that would both help maintain its coolness.

Saudi Arabia imports Thassos marble in the form of huge rock pieces, and they are processed in private Saudi factories under the supervision of qualified technical cadres to cut the rocks into tiles of specific sizes with special standards.