In recent years Ive seen a rather different-appearing material
(very attractive!) with blobby red inclusions in highly
transparent clear quartz offered as lepidocrosite (in quartz).
Over the years, Lapidary Journal has run several q&a articles on
quartz gems and the subject of what’s that stuff inside comes up in
most of them. In July 1999 (“More Wine!” – 10 more questions on
amethyst), Si & Ann Frazier discuss some of these reddish inclusions
that have been called lepidocrocite, and suggest that these, too, are
most likely hematite. (Questions 5, 6, and 7). In November 1998
("Rutilated Q&A), they cover similar ground in Question 7.