Our Indian Stone - where does it come from?

Our Indian Stone - where does it come from and how is it formed?

So you’re looking to get yourself a beautiful patio, but what is the story behind the stone itself? Some of our most popular products are our Indian Sandstone and Limestone, so we thought it was time to learn a bit more about them. We spoke to one of our suppliers who is based in India,  and whose knowledge on the subject is something to behold. 

Where does it come from?

Raj Green is the most popular of our Indian sandstones and gets its name from the northern city in which it was originally discovered, Rajpura. Its colouring consists of subtle greens and browns, and as these same colours were being discovered outside of Rajpura the name stuck.

Raj Green is now quarried alongside our other popular colours such as Kandla Grey, Autumn Brown and Camel/Rippon Buff, all within an 80-kilometre radius of the central-northern city of Kota. Once quarried, the stone is categorised into colour groups based on their varying grey, brown and beige hues. Kandla Grey specifically is named after the port from which most of our Indian sandstone is exported. 

Our stunning limestone Ocean Kota Blue is quarried in the south and Midnight Kota Black specifically in the southern town of Kadapa. Can you guess where Kurnool Grey comes from? That's right, it is quarried in Kurnool which is also in the south. Interestingly, there is quite a clear divide between the colour hues found between the north and the south of India, with more blues, greys and blacks being found in the south.

What is the industry like in India?

The stone industry in India is largely responsible for sourcing granite, sandstone and limestone. In one year, £110,000,000 worth of stone is shipped from India to Europe and the UK. Exports make up only around 7% of the volume of stone quarried, which is largely used domestically in India for roofing and flooring. The stone industry employs around 4 million people across Rajasthan and Southern India, so it really is a booming industry. 

Traditionally, much of the work in quarries was done by hand, but technological advances have really improved working conditions. Machines built for drilling and heavy lifting make the quarrying process much quicker, easier and safer. However, manual labour remains a traditional part of the industry as a lot of skill goes into hand-cutting our paving. Sandstone and limestone are formed in layers which are carefully split by hand to produce the popular riven texture found on our slabs. 

How is the stone formed? 

Sandstone

The clue is in the name with this stone, forming over thousands of years from grains of sand produced in the physical and chemical and weathering of bedrock (i.e. the rock resting at the earth’s surface, most prevalent in volcanic or mountainous areas). These grains of sand are transported from their source by wind or water, and are eventually deposited in a ‘sedimentary environment’. In this continual process, younger sand lands on top of older sand, and this increased pressure causes the sand to compact and the grains merge into a hard stone. 

Sandstone’s characteristic layered appearance is a result of varying pressures, temperatures, sand types and environmental conditions. Compaction occurs to different extents as the sand particles are buried deeper and deeper, creating different density and physical appearance between layers. Different colours and textures are a result of varying levels of silica and quartz in the sand, and these can be determined in petrographical tests which are conducted by our supplier.

Limestone

The formation process is slightly more complex when it comes to limestone. In shallow and warm waters when marine life dies, shells, skeletons, algae, and even fecal matter fall to the water's bed. As these are compressed over thousands of years, they become hard and form biological limestone which can be identified by the presence of fossils within the stone. The chemical process is similar, as calcium carbonate precipitate falls to the seafloor and is compacted over thousands of years. In caves, mineral-rich water permeates the rock and drips from the cave's ceiling. The water evaporates and solid mineral calcium carbonate is left behind to form limestone stalactites and stalagmites. 

Hopefully, by now you will have learned a bit more about our beautiful handcrafted stone products. We certainly enjoyed finding out where it all comes from! 

Now, time to get that new patio sorted...