Portland Stone limestone was formed from calcium carbonate in the bottom of an ancient tropical sea. Portland Stone limestone is naturally beautiful and provides a rich, substantial appearance. Quarried in United Kingdom, Portland Stone limestone is most suited for interior applications and protected exterior locations. The calcium carbonate crystals in Portland Stone limestone allow it to be polished. When used as StonePly panels, limestone is strong and easy to handle and install.

Portland Stone limestone originally formed at the bottom of an ancient, shallow tropical sea. Calcium carbonate forms and builds up around grains of sand or pieces of shells or coral, cementing them together. Over time limestone is formed. Portland Stone limestone is quarried in United Kingdom. The beautiful soft tone of Portland Stone is prized for architectural stone panels. With StonePly panels the aluminum panel strengthens the limestone. In fact Stoneply panels have 60 times the impact strength of un-reinforced limestone panels.