Assertion: mineral's set | /r/CapableOf | add to complication
Facets:
Source sentences:
text: In publications, two different sets of Miller indices are used to describe directions in calcite crystals - the hexagonal system with three indices h, k, l and the rhombohedral system with four indices h, k, l, i. To add to the complications, there are also two definitions of unit cell for calcite.