Sands & Aggregates
Sands and Stonedust, also known as aggregates, when mixing into a mortar perform very important functions within the mix. The high shrinkage of pure putty lime is overcome by mixing with well graded and angular sands. There is a wide range of sand types available, ranging from the finest white sand to coarse dark grits and gravels. Sands are usually mixed and graded at the quarry to satisfy British Standards. We also blend and create a variety of different sands that are known as ‘blended sands’. These can also contain various Stonedusts aswell to help plasticise and create colour variations. Stonedusts are usually crushed and sieved limestone. Although it is useful to have the air entraining properties of porous limestone in mortars, great care must be taken to avoid adding to much fine dust as shrinkage will occur. Construction, pointing mortar, plasters and renders have a high proportion of sand.