Skiddaw Slate (as opposed to Honister slate which has a green hue) and is used for building, in the Lake District. The traditional buildings of Keswick and other settlements are almost entirely of Skiddaw slate. The slate is also used for making souvenirs, monuments, ornaments etc. Smaller fragments are used for gravels or for ornamental pathways. Skiddaw Slate Skiddaw slate is an early Ordovician metamorphosed sedimentary rock, as first identified on the slopes of Skiddaw in the English Lake District. The base of this series is unknown. The thickness could, therefore, amount to several thousand feet of sediment. These sediments were formed
Physical change an alloy can be difficult and may require chemical processing – making an alloy is an example of a physical change that cannot readily be undone by physical means. Alloys where mercury is one of the metals can be separated physically by melting the alloy and boiling the mercury off as a vapour. Physical change Physical changes are changes affecting the form of a chemical substance, but not its chemical composition. Physical changes are used to separate mixtures into their component compounds, but can not usually be used to separate compounds into chemical elements or simpler compounds. Physical changes occur