Kandla Grey Sandstone: A Paving Guide for European Hardscaping

Kandla Grey is the most-laid Indian paving stone in Europe. It is also the stone whose name teaches you the most about how the trade works.

It does not come from Kandla

Verified origin: Bijolia in Bhilwara district, Rajasthan, with Bundi and Khadhipur in the same belt.

Kandla is a port in Gujarat, several hundred kilometres away. The stone is called Kandla Grey because that is where it left India, not where it came out of the ground.

This is not a scandal — port names attach themselves to commodities all over the world. But it is a useful test. Ask a supplier where Kandla Grey is quarried. If they say Kandla, or Gujarat, they are repeating a label rather than describing a supply chain. If they say Bijolia, in Bhilwara, they have been there or they have records that go back to the quarry.

International aliases: Silver Grey Indian, Autumn Grey.

Why it dominates

The colour is genuinely useful. A soft, even blue-grey that works with brick, render, timber decking, contemporary rendered extensions and traditional stone alike. It is the neutral of European hardscaping.

It is dense for a sandstone. Denser than the exotic Rajasthani sandstones, which matters in a freeze-thaw climate.

Supply is deep. The Bijolia–Bundi belt has enough working quarries to serve European volume without allocation games.

It weathers to something better. Fresh Kandla Grey is slightly warm; after a season it settles into a cooler, more silver tone that most people prefer to the new stone.

The tonal range problem

Here is the practical issue every Kandla Grey buyer meets.

Kandla Grey is not one grey. It runs from a pale silver through a mid blue-grey to a darker, browner grey, sometimes with rust-brown banding. Within one quarry it drifts between benches; across the belt it drifts a lot.

Some of the trade sells "Kandla Grey" and some sells "Kandla Grey (Premium / Select)" meaning the tighter tonal band, with the wider band sold cheaper. Neither is wrong. Buying one when you specified the other is the problem.

What to do:

1. Approve a physical range panel — five or six pieces showing the acceptable spread from palest to darkest, including the maximum acceptable brown banding. Seal it, date it, hold a copy at each end.
2. Lay from a blended pallet. Even within an approved range, laying crate by crate produces visible patches. Blend across three or four crates as you lay. Put this in your installation guidance to your customers.
3. Do not promise repeat matching. A second delivery six months later will sit inside the range but will not be identical. Tell the client at the point of sale.

Formats

Calibrated slabs — machine-calibrated to consistent thickness, usually 22 mm or 30 mm, sawn edges. The dominant European format because it lays fast on a bonded or unbound bed. Get the tolerance in millimetres, in writing.

Hand-cut / riven — natural cleft face, hand-dressed edges, thickness in a band rather than at a value. Cheaper per square metre, slower to lay, traditional look.

Tumbled / antiqued — softened edges and surface. For courtyards and heritage-adjacent work.

Sizes. European work uses 600×600, 600×400, 900×600, 1200×600 and free-length planks. UK patio packs use imperial-derived sizes in a planned ratio — buy the pack, not the sizes, because the ratio is the product.

Setts, kerbs and steps in the same stone. Order them with the paving, from the same block run, or the level changes will not match. See Indian Sandstone Setts, Kerbs and Cobbles.

Test data — what to insist on

EN 1341 is the harmonised standard for slabs of natural stone for external paving. Products under it require a Declaration of Performance. Kerbs are EN 1343, setts EN 1342.

The individual tests that matter:

The before-and-after flexural comparison is the one that matters. A sandstone can survive 48 freeze-thaw cycles with no visible damage and have lost a third of its flexural strength. On a bedded patio that may never show. On a pedestal-mounted terrace it does.

Kandla Grey generally performs well on these tests relative to the exotic sandstones. That is a reason to ask for the data, not a reason to skip it — and the numbers are quarry-specific, not stone-specific.

Full treatment: Frost-Resistant Indian Sandstone Paving for Cold Climates.

Slip resistance by market

• UK — a wet PTV per BS 7976. UK Slip Resistance Group guidance treats 36 and above as low slip potential.
• Germany — DIN 51130 R-classification (R9–R13) for general and workplace floors; DIN 51097 classes A/B/C for barefoot wet areas.
• Netherlands and Belgium — EN 14231 USRV, with project-specific requirements.
• Australia — AS 4586 P-classification.

Get the figure for the finish you are ordering. Riven Kandla Grey and sawn-and-brushed Kandla Grey are different products in slip terms.

Responsible sourcing — the Benelux question

For Dutch and Belgian buyers, this is not optional. TruStone is the covenant governing responsible sourcing of natural stone in the Netherlands and Belgium, and participants have obligations that reach back through the supply chain to the quarry.

Kandla Grey is squarely in scope. See TruStone-Compliant Indian Sandstone: Responsible Sourcing for Public Paving.

For German buyers, the equivalent question is XertifiX or Fair Stone certification — see Selling Stone to Germany.

Both require the same foundation: a supply chain that terminates in a named quarry. "Rajasthan" cannot be audited. Bijolia can.

Laying and aftercare

Full mortar bed or properly compacted unbound construction, with drainage falls that actually work. Most sandstone terrace failures in freeze-thaw climates are water management failures.

Prime the back of calibrated slabs where bonding to a wet bed — standard practice, frequently skipped.

Efflorescence is normal on new Indian sandstone as salts migrate out, and weathers off over a season or two. Tell the client in advance and it is a characteristic; afterwards it is a complaint.

Iron spotting. Some sandstone carries iron inclusions that rust-stain. Ask for slabs to be photographed wet, which is when it shows.

Sealing reduces absorption and staining. It does not make a porous stone frost-proof, and should never substitute for frost data.

What to ask a supplier

1. Where is this quarried? The answer should be Bijolia, Bundi or Khadhipur — not Kandla.
2. Which quarry, specifically, and can it be held for a repeat order?
3. Range panel approved, sealed and dated at both ends.
4. Calibration tolerance in millimetres.
5. EN 13755, EN 12371 and EN 12372 before and after cycling, for that quarry.
6. Slip figure in the form my market asks for — PTV, R-class, USRV or P-class.
7. Declaration of Performance under EN 1341.
8. Responsible sourcing position — TruStone, XertifiX, Fair Stone, or a named auditable quarry.
9. How is it packed? Sandstone chips at the arris and stains from wet timber — Sea Packing for Natural Stone.

What Gemarix does differently

We name the village, and on this stone specifically we correct the trade's own label. Kandla Grey is Bijolia, in Bhilwara district. Raj Green — sold in Britain as Raveena — comes from the same Bijolia–Bundi–Khadhipur belt. Autumn Brown too.

For a Dutch, Belgian or German buyer who has to demonstrate where their paving came from, that is the whole difference between a supply chain and a shipping label.

Frequently Asked Questions

Where is Kandla Grey sandstone quarried?

At Bijolia in Bhilwara district, Rajasthan, with further quarries at Bundi and Khadhipur. Kandla is a port in Gujarat several hundred kilometres away, so the name records how the stone left India rather than where it came from.

Why does Kandla Grey vary in colour?

Because it is not one grey. It runs from pale silver through mid blue-grey to a darker, browner grey, sometimes with rust-brown banding, and it drifts between benches within a quarry as well as across the belt. Approve a range panel showing the acceptable spread rather than a single sample.

Should Kandla Grey be laid from one crate at a time?

No. Even within an approved range, laying crate by crate produces visible patches. Blend across three or four crates as you lay, and put that instruction in the guidance you give your own customers.

What thickness does Kandla Grey come in?

Calibrated slabs are usually 22mm or 30mm with sawn edges, which is the dominant European format because it lays fast on a bonded or unbound bed. Hand-cut or riven material is supplied in a thickness band rather than at a value.

What test data should I ask for on Kandla Grey?

EN 13755 water absorption, EN 12371 frost resistance with the cycle count stated, and EN 12372 flexural strength measured before and after the frost cycling. Add the slip figure in the form your market uses, and a Declaration of Performance under EN 1341.