Sentence examples for hard mineral from inspiring English sources

Riebeckite is a moderately hard mineral with a glassy lustre.

Because they are soft-bodied animals, tunicates have left little fossil record apart from the hard mineral particles, called spicules, that are found in the tunics of some species.

(Tourmaline is an extremely hard mineral that, when built into the components of a dryer, supposedly speeds up the drying process by about 60 percent and cancels out static electricity).

In 1674 Ravenscroft obtained a seven-year patent for a glass with the desirable quality of a resemblance to rock crystal; this glass was made from a formula including transparent black flint (a hard mineral of the quartz family), which he called "flint crystalline".

And ferroelectricity was reported last year in the hard mineral coating of seashell.

Hard mineral grains (quartz, feldspar, and calcite) in gray (at the top) and pyrite (at the middle-right) occur in chains.

But hardrock miners, who extract hard minerals rather than hydrocarbons, pay no royalties on the $1 billion worth of metals and gems they extract annually.

The Cornish presence in this remote spot goes back to the days when Cornwall was known (as Poldark reminded us) for copper and tin mines, and Cornishmen were famed as the most skilful hard-mineral miners in the world.

The gulf's natural resources include offshore oil deposits and deposits of hard minerals within the continental shelf.

The geology of the region — hard volcanic rock infused with other extremely hard minerals — favored the Plan B equipment, said Maurice B. Dusseault, a professor of engineering geology at the University of Waterloo in Canada.

Particle roundness or angularity also reflects mineralogy (soft minerals are abraded more readily than hard minerals), clast size (coarse particles become rounded more rapidly than do fine ones), and transport distance (sands become more abraded and hence rounder as the distance traveled increases).