From Longman Dictionary of Contemporary Englishlapis lazulilap‧is laz‧u‧li /ˌlæpəs ˈlæzjʊli $ -ˈlæzəli/ noun 
[countable, uncountable]DCJ a valuable bright blue stone, used especially in jewellery
[countable, uncountable]DCJ a valuable bright blue stone, used especially in jewelleryExamples from the Corpus
lapis lazuli• Outside the light was dazzling, the sky as blue as lapis lazuli.• The staircase and walls are of white marble, with the addition of lapis lazuli for the geometrical floor pattern.• A ripple of lapis lazuli and there was no sign of it.Origin lapis lazuli (1300-1400) Medieval Latin Latin lapis “stone” + Medieval Latin lazuli “of lapis lazuli” (from Arabic lazaward) 