Wiktionary
n. (context mineral English) A blueish-green form of mica.
Wikipedia
Celadonite is a mica group mineral, a phyllosilicate of potassium, iron in both oxidation states, aluminium and hydroxide with formula: K(Mg,Fe)(Fe,Al)[SiO](OH).
It crystallizes in the monoclinic system and usually forms massive aggregates of prismatic crystallites or in dull clay masses. It is soft with a Mohs hardness of 2 and a specific gravity of 3. Typically occurs as dull gray-green to bluish green masses. It forms vesicle fillings and linings in altered basaltic lavas.
It was first described in 1847 on Mt. Baldo, near Verona, Italy. The name is from the French celadon, for sea-green.
Usage examples of "celadonite".
I could have called out and initiated a deep argument about crushed malachite (which is so expensive) as against green earth celadonite (which fades), but who wants to start libelling "Appian green' with a painter who is known to thump people?