A graphic representing decorative aggregate grading, showing stone falling through different size mesh sieves

Decorative aggregates are graded mechanically by size using sieves with selected mesh dimensions. Any screening process can only separate the stone using two of the three dimensions of height, width and length.

Stone Warehouse products will contain a portion of stones with a dimension that is outside of the specified product dimensions, with the 3rd dimension normally being longer depending on how the stone has passed through the sieve. There can also be a minimal quantity of stones of a smaller size that have made their way through the sieve during the grading process. This is to be expected and within the British Standard tolerance of 8% for aggregates coarser than 10mm, and up to 20% between 5 – 10mm

Some products may not mention their size range within their title. This can be found within the ‘Product Information’ tab on its individual page. For example, Golden Gravel 20mm will have a size range of 14–20mm displayed in the ‘Product Information’ tab.



Stone is graded on its ‘narrow’ side and the other dimension can be considerably larger, as shown in the example below:

Although we try our best to reflect the size of our products within their imagery, this doesn’t always appear physically true to size. Images can also be displayed differently depending on the type of device that you are viewing them on. We always recommend ordering a sample to ensure that you’re happy with the size and colour of the product before placing an order.




A montage image, showing different sizes of Gravel & Chippings, Pebbles & Cobbles for comparison

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