[1] : The Collaborative International Dictionary of English v.0.48

geyserite \gey"serite\ gimac"z~erimact or
   gimac"s~erimact; 277, n. from geyser. min.
   a loose hydrated form of silica, a variety of opal, deposited
   in concretionary cauliflowerlike masses, around some hot
   springs and geysers.
   1913 webster
see also:
geyser 

[2] : The Collaborative International Dictionary of English v.0.48

opal \o"pal\, n. l. opalus: cf. gr. ?, skr. upala a rock,
   stone, precious stone: cf. f. opale. min.
   a mineral consisting, like quartz, of silica, but inferior to
   quartz in hardness and specific gravity.
   1913 webster

   note: the precious opal presents a peculiar play of colors
         of delicate tints, and is highly esteemed as a gem. one
         kind, with a varied play of color in a reddish ground,
         is called the harlequin opal. the fire opal has
         colors like the red and yellow of flame. common opal
         has a milky appearance. menilite is a brown impure
         variety, occurring in concretions at menilmontant, near
         paris. other varieties are cacholong, girasol,
         hyalite, and geyserite.
         1913 webster
see also:
precious opal harlequin opal fire opal common opal menilite cacholong 
girasol hyalite geyserite 

Geyserite >> G Words
Geyserite, definition of term: Geyserite
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