Grey cement or simply cement is a binder in construction work. Cement is mixed with sand, gravel or crushed stones and water to form concrete. When it comes to constructing buildings, concrete is used to build foundations, beams, columns, slabs, load-bearing walls, etc.

Clinker is the main constituent of cement. It is a nodular material produced in the pyroprocess stage of cement production and to the untrained eye, clinker looks like small grey rocks a few centimetres in diameter.

Gypsum is a mineral found in crystal as well as masses called gypsum rock. It is a very soft mineral and it can form very pretty, and sometimes extremely large colored crystals. Massive gypsum rock forms within layers of sedimentary rock, typically found in thick beds or layers.

Iron ore is a mineral substance which, when heated in the presence of a reductant, will yield metallic iron (Fe). It almost always consists of iron oxides, the primary forms of which are magnetite (Fe3O4) and hematite (Fe2O3). Iron ore is the source of primary iron for the world’s iron and steel industries.

Limestone (calcium carbonate CaCO 3) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of CaCO 3. Limestone forms when these minerals precipitate out of water containing dissolved calcium.

White cement can be used in numerous applications, including tile grouts, cementitious paint, terrazzo, pavers, precast concrete, decorative projects, and more.

Sand, gravel and crushed stone are all considered to be aggregates. More simply, aggregates include grains or fragments of rock. They are a non-renewable resource which we benefit from daily, but rarely think about.

Slag usually refers to a glassy by-product of smelting ores to retrieve the metal. I use the term here to also include any man-made, rock-like by-product of heating things to high temperature. Thus, clinkers are a form of slag. Slags catch people attention because of their morphology.

Gabbro is widely used as crushed stone for concrete aggregate, road base material, and railroad ballast. Smaller quantities are cut and polished for dimension stone and called black granite.