The Chemical Composition of Lunar Soil
As a lunar geochemist I have been approached many times by people who believe that they have a sample from the Moon. Common stories are (something like) “This dust was given to my late grandfather by astronaut Buzz Lightyear” or “This rock that I found in my petunia pot looks just like lunar meteorite QUE 94281 on your website.” Lately, people have been sending me reports that they have obtained of chemical analyses from labs or one of those hand-held x-ray “guns.” So, here is what you need to know in order to interpret those reports.
Major Elements – In lunar rocks and soils 99% of the mass
consists of the following 7 chemical elements
Oxygen (41-45%) | Silicon (Si) | Aluminum (Al) | Calcium (Ca)
Iron (Fe) | Magnesium (Mg) | Titanium (Ti)