Stones can have many aliases. This is due to language differences, supplier choice, coloquial trends or slang, or sometimes errors and ambiguity between rocks. Read more here.
|Finlandia Blue, Finnish Labrador|
Commercial classification sometimes differs to the scientific, geological designation. In particular, some limestones are deemed marble especially if they take a high polish. Read more here.
|Age||900 million years (Precambrian)|
|Colouring minerals:||Black-blue labradorite feldspar, grey-beige feldspar, black pyroxene|
MOHS is the standard scale of hardness for minerals 1-10, with 10 being the MOHS of diamond. We also use the broad terms Hard and Soft for simplicity. Read more here.
Petrology:– a sub-group of the gabbro family, anorthosites are medium to large grain plutonic rocks and. They have a basic black-green shading and consist of labradorite-feldspar. The labradorite crystals of spectrolite show, due through sub-microscopic fine segregation lamella, shimmering light reflections in every colour of the spectrum – but predominantly blue.
Petrogenesis:– Anorthosites usually exist as bands, lenses and layers in large gabbro massifs. On the then Scandinavian Shield, during the Algonkian period (primeval ages), the anorthosite component separated from the gabbro magma through crystallisation over millions of years, then solidified as spectrolite with coarse crystals to giant grains.