e/Blue ground

Information
has gloss	eng: In reconnaissance for diamond mining, blue ground refers to a layer of nonoxidized kimberlite. Kimberlites are a class of igneous rocks most commonly associated with diamond mining. Before the advent of modern geophysical probes, the ideal way to find a kimberlite pipe, a prime location for finding diamonds, was to search for "yellow ground", a layer of oxidized kimberlite which, perhaps not surprisingly, is a deep tawny yellow. "Blue ground" was regarded with scorn during the South African diamond rushes, and one of the central characters in the initial diamond rush, Barney Barnato, made his fortune by purchasing digs in which the "blue ground" was all that was remaining.
lexicalization	eng: blue ground
instance of	(noun) the part of the earth's surface consisting of humus and disintegrated rock dirt, soil

Meaning
Japanese
has gloss	jpn: ブルーグラウンドは鉱業の用語で、主にダイヤモンドの鉱床であるキンバーライト（岩石名）が酸化されていない土壌のことを言う。酸化していないキンバーライトが青く見えることから、こう呼ばれる。
lexicalization	jpn: ブルーグラウンド