Formula: CaB(SiO₄)(OH)

Species: Silicates – (Nesosilicates)

Colour: White, greyish, pale green, red, yellow, pink, etc.

Lustre: Vitreous, Resinous

Hardness: 5 – 5½

Specific Gravity: 2.96 – 3.00

Crystal System: Monoclinic

Member of: Datolite Subgroup > Gadolinite Group > Gadolinite Supergroup

Name: Named in 1806 by the Danish-Norwegian geologist, Jens Esmark (1762-1839) from the Greek δατεῖσθαι for “to divide”, in reference to the granular texture of massive varieties.

Type Locality: Nødebro Mine (Nøddebro), Øyestad, Arendal, Agder – Norway

Commonly formed by hydrothermal or volcanic processes.Compare also the closely related shimazakiite.