4 Pages in Charles Darwin's Library associated with "geology - opal"

Manual of mineralogy
By: Jameson, Robert.
Publication info: Edinburgh, Archibald Constable & Co, 1821
Pages: Page 210 Page 210
Principles of geology
By: Lyell, Charles, Sir,
Publication info: London, John Murray, 1837
Volume: v.4
Pages: Page 373 Page 374