1) Calcium mineral 2) Trigonal mineral
Found on
https://www.crosswordclues.com/clue/portlandite
Portlandite is a rare oxide mineral, the naturally occurring form of calcium hydroxide (Ca(OH)2). It is the calcium analogue of brucite (Mg(OH)2). ==Occurrence== Portlandite occurs in a variety of environments. At the type location in Northern Ireland it occurs as an alteration of calc-silicate rocks by contact metamorphism of larnite–spurrite. ...
Found on
http://en.wikipedia.org/wiki/Portlandite
No exact match found.
