The close-up view of each stone type shows a relatively true image of the crystalline structure and the colouring. This is suitable for grained slabs to a limited extend only. In regard to the colour matching, please take an original sample of the stone from your furniture store as a basis.
This gneiss consists mainly of brown feldspar the content of bright, transparent quartz is very low.
This gneiss was generated under high pressure and temperature from plutonic rock with syenitic composition. Only the structure was changed by the metamorphosis but not the mineral content. The formerly undirected arranged crystallites were "rolled out? and largely arranged in parallel.
|Structure Type||Homogeneous Structure|
|Age||Older than 570 m. years (probably Pre-Cambrian)|
|Colouring Minerals||Brown alkaline field spar, black biotite|
|Average Hardness||6-7 (According to Mohs's hardness scale 1-10)|