An alloy is a mixture of metals or a mixture of a metal and another element.Alloys are defined by metallic bonding character.An alloy may be a solid solution of metal elements (a single phase) or a mixture of metallic phases (two or more solutions). Intermetallic compounds are alloys with a defined stoichiometry and crystal structure.he term alloy is used to describe a mixture of atoms in which the primary constituent is a metal. The primary metal is called the base, the matrix, or the solvent. The secondary constituents are often called solutes.
Marl or marlstone is a calcium carbonate or lime-rich mud or mudstone which contains variable amounts of clays and silt.
RAL is a colour matching system used in Europe. In colloquial speech RAL refers to the RAL Classic system, mainly used for varnish and powder coating but nowadays there are reference panels for plastics as well.Approved RAL products are provided with a hologram as of early 2013 to make unauthorised versions difficult to produce.n the 1930s the numbers were changed uniformly to four digits and the collection was renamed to RAL 840 R (R for revised). With tints constantly added to the collection, it was revised again in 1961 and changed to RAL 840-HR, which consists of 210 colors and is in use to this day.