Changesite-(Y)
A rare-earth-bearing phosphate discovered in Moon rock returned by Chang'e 5.
Key facts
- Formula
- (Ca8Y)Fe(PO4)7
- Family
- Phosphates
- Crystal system
- Trigonal
- First described
- Chang'e 5 lunar samples, 2022
Changesite-(Y) was described in 2022 from basalt fragments in the Chang'e 5 soil, the first new mineral found by China in a lunar sample. It is named after the Chang'e programme, and the (Y) shows that yttrium is its main rare earth element.
What it is
Changesite-(Y) is a phosphate of calcium and iron with yttrium, related in structure to merrillite. It formed in the last pockets of melt in a lunar basalt.
Where it is found
It was found as tiny clear columnar crystals in a basalt particle from the Chang'e 5 samples, which come from lava about 2 billion years old.
How it is recognised
It was identified by single-crystal X-ray diffraction on a grain about 10 micrometres across.
Did you know?
It was the sixth new mineral discovered in lunar samples.
Its crystals are about a tenth of the width of a human hair.