geode
(ˈdʒiːəʊd)
Also 8–9 geod.
[a. F. géode, ad. L. geōdes = Gr. γεώδης earthy, f. γῆ earth.]
A concretionary or nodular stone, containing a cavity usually lined with crystals or other mineral matter.
| [1619 R. C. Table Alph., Stones, Geodes, a stone being hollow, having earth within the hollownesse thereof, and being put to a mans eare, it maketh a kinde of sound.] 1676–1732 Coles, Geode, the Earth-stone. 1774 Strange in Phil. Trans. LXV. 41 A hard ferruginous substance, of a dark-brown colour, much resembling some common ferruginous geodes I have seen. 1811 Pinkerton Petral. I. 436 Infiltrated geods of quartz and calcareous spar. 1839 Murchison Silur. Syst. i. vii. 107 Each geode being enveloped in red shale. 1860 O. W. Holmes Prof. Breakf.-t. 71 An aphorism..has been forming itself in one of the blank interior spaces of my intelligence, like a crystal in the cavity of a geode. 1883 L. Oliphant Haifu (1887) 37 A plateau..abundantly strewn with geodes. |
b. The cavity itself, together with the crystal or mineral formation therein contained. Also any similar formation.
| 1849 Dana Geol. iv. (1850) 298 Small geodes of stilbite and analcime were found in pebbles. 1831 Raymond Mining Gloss., Geode, a cavity, studded around with crystals or mineral matter. |
Hence geoˈdiferous a. [-iferous], producing or abounding in geodes; ˈgeodize v. [-ize], trans., to convert into a geode; ˈgeodized ppl. a.
| 1847 Craig, Geodiferous. 1885 Amer. Jrnl. Sci. Ser. iii. XXX. 376 The geodized fossils of the Keokuk limestone. |