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Aventurine glass is typically (though not always) green with copper/gold colored flecks.
Aventurine is also the name of a semi-precious stone. The distinguishing feature of aventurine stone, like the glass, is the metallic fleck inclusion.
Folklore has it that aventurine glass was invented by accident when a Murano glass artist spilled copper filings into the glass batch. The glass that resulted from that happy mistake was named aventurine -- a ventura is Italian for by chance.
Ironically, the natural stone aventurine is named for the glass that mimics the stone's appearance.