| 1. | an opaque, brown glass containing fine, gold-colored particles. |
| 2. | any of several varieties of minerals, esp. quartz or feldspar, spangled with bright particles of mica, hematite, or other minerals. |
aventurine
either of two gem minerals, one a plagioclase feldspar and the other quartz. Both have a sparkling reflection from oriented minute inclusions of mica or hematite.
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