Why stone color changes between batches, and how to protect your facade from it

You pass a handsome villa in Amman and notice that the second floor is lighter, or more yellow, than the first. Nobody meant it. The stone is from the same quarry with the same name, but from two batches.

Natural stone is not a manufactured product

A quarry is a hill of layers laid down over millions of years. Each layer has a different share of iron, clay and fossils, so its color differs slightly: whiter, more yellow, or with clearer veins. As cutting advances through the quarry over months, it moves from layer to layer.

Ma’an stone, for instance, ranges from ivory white to beige depending on the layer and grade, and Ajloun from cream to gold. One name, not one color.

How the mistake happens on a facade

The usual way: the contractor orders stone in deliveries as the building goes up. The first delivery for the ground floor, the second two months later for the first floor. Between them the cutting layer has changed, or the supplier has, and the second arrives in another shade. The difference does not show on a pallet, but it shows clearly on an eight-meter wall in midday light.

The answer: one batch, one sort

We work the other way round:

1. We calculate the whole quantity first, including waste, from the calculator or your drawings.
2. We cut all of it from the same quarry and the same layer in one period.
3. We sort the pieces on the ground and set aside the odd colors.
4. We send you photos of the pallets before loading.
5. We deliver the whole quantity before installation starts, on wrapped and covered pallets.

The result is that the mason draws from all the pallets in turn, so the light natural gradation spreads across the whole facade instead of collecting on one floor.

Tips for the site

• Store the pallets covered, away from mud and mixing water.
• Ask the mason to work from three pallets at once, not one pallet until it is empty.
• Do not buy a "top-up" from another supplier; if you must, ask us for it from the same reserved batch.

This is the difference we mean by one color, one batch. See the stones and their gradations in the stone guide.