XLPE compound of Sioplas method for cable can also include calcium carbonate as a filler. Calcium carbonate is a common filler used in wire and cable applications to improve the mechanical and electrical properties of the insulation. It can also help to reduce the cost of the compound by replacing some of the more expensive materials, such as XLPE or other high-performance polymers. Calcium carbonate is typically added in small amounts, usually less than 10% by weight, and can improve properties such as tensile strength, modulus, and thermal stability.