bluestone

Short definition from Wiktionary

Noun

1. 1
   Any of several bluish-grey varieties of stone used for construction
2. 2
   Any of several bluish-grey varieties of stone used for construction: A form of dolerite which appears blue when wet or freshly broken.
3. 3
   Any of several bluish-grey varieties of stone used for construction: Any of the several (massive) kinds of non-local stone (particularly dolerite) used to construct Stonehenge.
4. 4
   Any of several bluish-grey varieties of stone used for construction: A feldspathic sandstone found in the US and Canada.
5. 5
   Any of several bluish-grey varieties of stone used for construction: A form of limestone found in the Shenandoah Valley and some other places.
6. 6
   Any of several bluish-grey varieties of stone used for construction: A bluish-grey basalt or olivine basalt.
7. 7
   Any of several bluish-grey varieties of stone used for construction: Slate, such as comes from quarries in or near Adelaide.
8. 8
   Either of two related copper- and sulfur-based bright blue stones: Copper(II) sulfate, CuSO₄(H₂O)ₓ where x is 0-5, used as a coloring agent in glass-making and pottery and for other purposes.
9. 9
   Either of two related copper- and sulfur-based bright blue stones: Chalcanthite, a water-soluble sulfate mineral, CuSO₄·5H₂O.
10. 10
    Lapis lazuli, or its core constituent, lazurite.

Verb

1. 1
   To treat or dose with copper sulfate.

Proper noun

1. 1
   A surname.