There is a blue-green that seems to belong to a place between sea and sky. Grandidierite brings me towards that quieter territory. I want its colour to have depth, with enough small variations inside it to reward a second look.
The material and its origins
Grandidierite is a magnesium-aluminium borosilicate, first described from southern Madagascar in 1902. Gem-quality material is extremely rare, with important finds around Tranomaro in Madagascar and documented facetable material from Sri Lanka. Its pleochroism means that different viewing directions can reveal different colours; this differs from alexandrite’s response to changing illumination.
| Material | Borosilicate |
|---|---|
| Mohs hardness | 7.5 |
| Optical character | Blue-green colour and directional colour variation |
What it brings to my work
For me, its significance lies in quiet discovery. I would use it as a passage of concentrated colour within a larger work, letting the blue-green hold the eye without overwhelming the surrounding forms. The sense of hidden water is a visual association, rather than a claim about where the mineral formed.