The most common constituent of sand, in inland continental settings and non-tropical coastal settings, is silica (silicon dioxide, or SiO 2), usually in the form of quartz, which, because of its chemical inertness and considerable hardness, is the most common mineral resistant to weathering.
THE FIRM. TAN KOK QUAN PARTNERSHIP is a full service law firm providing legal services across a broad spectrum of industry sectors. Our firm's principal founder and first managing partner was Tan Kok Quan, Senior Counsel, a well-respected litigator who was among the first batch of lawyers to be appointed senior counsel in Singapore.
Concrete, usually Portland cement concrete, is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens over time—most frequently a lime-based cement binder, such as Portland cement, but sometimes with other hydraulic cements, such as a calcium aluminate cement.