Spican flame gem
A Spican flame gem was a low value gemstone. 

In 2268, Cyrano Jones failed in an attempt to sell flame gems, along with Antarean glow water, to a bartender on Deep Space Station K-7. (, )

Jones would later attempt to sell some of the same flame gems to Captain Kirk in 2269 with similar results. ()

See also
 Rigelian flamegem

External link 
 

de:Flammenedelstein
Gemstones