These stones naturally have markings and inclusions.
There has been much contirversy concerning the nature and origin of the blue ground itself; and even granted that (as is generally believed) the blue ground is a much serpentinized volcanic breccia consisting originally of an olivine-bronzite-biotite rock (the so-called kimberlite), it contains so many rounded and angular fragments of various rocks and minerals that it is difficult to say which of them may have belonged to the original rock, and whether any were formed in situ, or were brought upfrom below as inclusions.
These include quartz inclusions, c. 0. 1mm across and possible sponge spicules, replaced by chalcedony.
Kliman and the team identified trophoblast inclusions by performing microscopic examinations of placental tissues.
This is typified by the presence of intracytoplasmic protein inclusions composed largely of alpha-synuclein fibrils.