. Bulletin - United States National Museum. Science. Figs. 7S-79.—78, Olivine. Vertically elongated crystal from black sand from Minidoka. Olivine. Crystal elongated on the o axis with the axial plane across the vertical elongation. The mineral is therefore optically biaxial and positive with X = 6, Y = c, Z=a; 2\ very large. The refractive indices are: a = , /3= , 7 = Several trials were made with various dilute acids with a view to dissolving out the calcite filling of the cavities in order to secure crys- tals for measurement. Practically all acids which dissolve the cal- c
. Bulletin - United States National Museum. Science. Figs. 7S-79.—78, Olivine. Vertically elongated crystal from black sand from Minidoka. Olivine. Crystal elongated on the o axis with the axial plane across the vertical elongation. The mineral is therefore optically biaxial and positive with X = 6, Y = c, Z=a; 2\ very large. The refractive indices are: a = , /3= , 7 = Several trials were made with various dilute acids with a view to dissolving out the calcite filling of the cavities in order to secure crys- tals for measurement. Practically all acids which dissolve the cal- cite attack the forsterite sufficiently to destroy the luster, but with acetic acid some measurable crystals were obtained, although they were so dulled as to give very poor measurements. The habit of these is shown in Figure 77 and they give the following forms and angles:. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original United States National Museum; Smithsonian Institution; United States. Dept. of the Interior. Washington : Smithsonian Institution Press, [etc. ]; for sale by the Supt. of Docs. , U. S. Govt Print. Off.
Size: 1451px × 1722px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorun, bookcentury1800, bookdecade1870, booksubjectscience
