Amethyst under polarized light Size:M: 60 x 45cm Plate 16 from the book

Plate 16 from the book Icones rerum naturalium

Jochen Mass

showing the intended Commercial and Collier Docks

28th September 1966

and the city must surrender soon

Amethyst under polarized light Size:M: 60 x 45cm Plate 16 from the bookSixteen figures showing specimens of amethysts viewed under polarized light and exhibiting veined structures. Brewster notes in his text: 'The observations are the result of an immense variety of experiments, which accidental circumstances put it in my power to make upon this interesting mineral. Having access to whole bagfuls of amethystine pyramids from the Brazils, in the possession of Mr Alexander, lapidary in Edinburgh, I have examined some