Autograph Letter Signed, to Professor Filippo Parlatore, the Italian botanist, apparently discussing the minerals to be found on Paul’s Island off the coast of Labrador, Canada. In Italian. 1¼ pages 10 x 8 inches, in good condition, a few minor blemishes, with the address leaf. Casa, 19 February 1846. Cesare Airoldi (1774-1858), Italian politician and naturalist, describes the blue and green tint of what is now known as Labradorite, a mineral which can have an iridescent effect.