Noun: bluestone 'bloo,stown
- Bluish-grey sandstone used for paving and building
"The historic district features pavements made of bluestone"
- Hydrated blue crystalline form of copper sulphate
"Gardeners use blue stone as a fungicide to protect plants";
- blue vitriol, blue copperas, chalcanthite
Derived forms: bluestones, blue stones
Type of: copper sulfate, copper sulphate [Brit, Cdn], cupric sulfate, cupric sulphate [Brit, Cdn], sandstone
Encyclopedia: Bluestone, Ohio
Blue stone