Xenotime is a rare earth phosphate mineral. According to Wikipedia, the rare earths dysprosium, erbium, terbium and ytterbium as well as metal elements such as thorium and uranium (all replacing yttrium) are the expressive secondary components of xenotime.
Much of Cale and Lane's Special Forces careers have been involved with China and preventing China from overrunning and destroying rare earth resources outside of China. Part of the plot in River and Ranch is centered on a south China "pirate" and his grandfather. They have built up a lucrative empire based on illegal mining of rare earth bearing ionic clays found throughout Guangdong province. As their empire has grown, they have become more protective of it. They send groups of saboteurs out to destroy newly discovered economic deposits of rare earth minerals in order to maintain their near monopoly on the "heavy" rare earth minerals.
Xenotime is one of those minerals in which the rare earths: dysprosium, erbium, terbium and ytterbium can reside.
What makes this interesting and hopefully fiction-worthy is the real life aspect of this. The entire rare earth topic is factual. China truly does have a huge problem with the illegal strip mining of ionic clays in Guangdong Province. The Chinese government has even gone so far as to create an industry group GRAD, intended to unite and control heavy rare earth oxide production in Guangdong Province. At least part of the intent of this industry group is to rein in the out-of-control and illegal strip mining of the rare earth bearing clays found throughout south China.
Zho Ming and his grandfather have hijacked GRAD and run it as a cover for their ongoing illegal efforts mining and selling heavy rare earth oxides to desperate and unscrupulous industrial clients. While Zho is fictional (as far as I know), the illegal strip mining and reselling of heavy REE oxides to western industrial clients is literally ripped from the headlines.
The real crime in all of this is the pollution that is being generated from the mining and processing of these ionic clays bearing the heavy rare earths that are so lucrative and in such high demand. China is rapidly creating its own cesspool of unlivable places, where no living thing can survive. No clean water, soil so polluted nothing grows and more. Much like the USA did in its infancy unfortunately. Or like the current mountain top strip mining for coal in West Virginia. Who are we to throw the first stone after all? Many of the miners doing the actual work in Guangdong Province are doing nothing more than trying to support their family. A truly interesting problem in many tragic ways, both for the earth and for humanity.
