<a href="https://en.wikipedia.org/wiki/Pegmatite" class="extiw" title="w:Pegmatite">Pegmatic</a> (about 30 mm) amphibole(?) <a href="https://en.wikipedia.org/wiki/Hornblende" class="extiw" title="w:Hornblende">hornblende</a> in <a href="https://en.wikipedia.org/wiki/Feldspar" class="extiw" title="w:Feldspar">feldspar</a>, from <a href="https://en.wikipedia.org/wiki/Custer,_South_Dakota" class="extiw" title="w:Custer, South Dakota">Custer, South Dakota</a>, in the <a href="https://en.wikipedia.org/wiki/Black_Hills" class="extiw" title="w:Black Hills">Black Hills</a>.
(corrections are invited)
<a href="//commons.wikimedia.org/wiki/User:IveGoneAway" title="User:IveGoneAway">IveGoneAway</a>
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