This is figure 3-20 of the <i>Apollo 15 Preliminary Science Report</i> (NASA SP-289, 1972), which has the following caption:<br>
The small white clast on top of the larger gray fragment located to the upper left of the gnomon is the <a href="https://en.wikipedia.org/wiki/Genesis_Rock" class="extiw" title="en:Genesis Rock">"genesis" rock</a> as the Apollo 15 crew found it on the lunar surface. It should be noted that this <a href="https://en.wikipedia.org/wiki/Anorthosite" class="extiw" title="en:Anorthosite">anorthositic</a> fragment is not in situ but occurs as a clast within a breccia. This sample was collected at station 7, <a href="https://en.wikipedia.org/wiki/Spur_(lunar_crater)" class="extiw" title="en:Spur (lunar crater)">Spur Crater</a>, on EVA-2.
NASA
1971
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