Otta Phyllite Riven Paving

Otta phyllite was first deposited as a thick sequence of muds and/or silts on the sea floor about 400-800 million years ago. We describe it as a "phyllite" yet, due to its high metamorphic grade, it is much harder and tougher than a normal phyllite. The natural surfaces are smooth and shiny due to biotite mica, a "mica-slate" in effect, yet are also sporadically studded with very hard metamorphic minerals, mainly hornblende (an amphibole) and garnet, which give Otta phyllite both its unique appeal and character and impart an extra degree of skid resistance. On weathering, the presence of iron oxide minerals can, on occasion, lead to oxidisation of some material to a pleasing golden hue. From the higher levels of the quarries, where there are 1-7% of iron oxide minerals, we supply Otta Rust where the original deep blue-black colour is tempered by scattered warm hues and shades of brown: buffs, pale to mid orange-browns and sepias.

Otta phyllite has been used in many exclusive projects, for example by Cartier for their 50 international stores, in many Porsche showrooms, NCC"s head office in Copenhagen and the Van Gogh Museum, Amsterdam, as well as Norwegian embassies worldwide.