diamond-sparn.
Etymology: < German demantspath (Klaproth 1786), so called from its extreme hardness.
Mineralogy.
1804 R. Jameson I. 93.
1807 J. Murray III. 593 The Diamond spar, which has been distinguished from corundum, appears to be a variety of it.
This entry has not yet been fully updated (first published 1895; most recently modified version published online June 2018).