What we have today are a few rock specimens — four to start with.
|Tourmalinized rhyolite porphyry from Majuba Hill: two fairly "fresh" or unmineralized samples on the left, and two mineralized versions on the right.|
|The first sample: a weathered surface of tourmalinized rhyolite porphyry. Tourmaline has replaced the feldspar phenocrysts, or filled voids left by the earlier leaching of feldspars, and left only the quartz eyes.|
|The second sample.|
|A second look at the second sample.|
We'll take a look at the next two samples some other day.