description: <p style="text-align: justify;">LOCALITY: Onganja Mine, Emke Farm, Namibia <br /><br />1 7/8" across <br /><br />This crystallized copper displays a combination of octahedral crystals and spinel law twins. Although this piece is copper red, I do not believe it has been dipped in acid. Copper from many localities (including Ajo, Arizona) is a similar color and the composition of the native copper alloy is one of the factors that influences the patina. <br /><br />Onganja is a small copper mine that no longer produces and few copper specimens were found there when it did produce.</p> <p style="text-align: justify;"> </p> <p style="text-align: justify;">This piece was traded from Marshall Sussman during a visit to his home in Tucson, Arizona in late 2012.</p> <p style="text-align: justify;"> </p> <p style="text-align: justify;">Photo  by Matthew Webb of Melbourne, Victoria, Australia </p> <p style="text-align: justify;"> </p>
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