Whilst the inherent quality of limestone was created by nature, Longcliffe have enhanced this through the application of pure science.
The quality of the base limestone deposits at Longcliffe are typically 99.5% pure calcium carbonate. This purity combined with sophisticated production techniques enables us to offer an unusually broad range of products – over 100 in all, from large natural block for monumental and building purposes, to granules for use in manufacturing processes which demand very high levels of purity, such as glass-making, and fine talc-like powders for applications such as rubber and carpet-backing.
Production involves a number of different steps. Firstly the rock face at the quarry has to be drilled and blasted to produce stone feedstock. This is taken to the plant where it undergoes a variety of processes including crushing, drying, milling, screening and, possibly, air classification, to produce a wide range of high quality aggregates, granules and fine powders (also known as ground calcium carbonates or GCC). Depending on the circumstances and intended uses, the order and necessity of those different steps vary.
Plant and machinery is constantly being upgraded. We pursue an active and substantial re-investment programme in all areas. Automation and computerised controls operate at all stages of the production process. All plant is monitored by computer to identify potential problems before they occur. If a problem is identified the system automatically closes down.
The company's limestone operations are centred on Brassington Moor quarry in Derbyshire, though we also produce dolomite aggregates, granules and powders from our at quarry at Ryder Point, Derbyshire.
Like with all mineral extraction processes, a resource like this is non-renewable, and the life of the quarry is ultimately finite. However with careful foresight, planning and investment, Longcliffe have secured reserves to enable us to continuing supplying the UK and global market places for high purity limestone and calcium carbonates well beyond the foreseeable future.