- Blue stone: lapis ... - Gem, lapis ... - Stone, lapis ... - A mineral of a fine azure-blue color, usually in small
rounded masses. It is essentially a silicate of alumina, lime, and
soda, with some sodium sulphide, is often marked by yellow spots or
veins of sulphide of iron, and is much valued for ornamental work.
Called also lapis lazuli, and Armenian stone.
- Blue precious stone - Gemstone that is blue and transparent - His paper has come out blue - Precious stone - september birthstone - Transparent precious stone - Native alumina or aluminium sesquioxide, Al2O3; corundum;
esp., the blue transparent variety of corundum, highly prized as a gem.