Glass Model

F. Krantz glass model (ca. 1900?)
Glass model of a monoclinic crystal (ca. 20 cm) from a series.
A small glued label indicates: "I | Dr. F. Krantz | Bonn a. Rh."

Internal silk threads materialize the crystallographic axes and illustrate with the corresponding colours the dispersion of the optic axes and of the acute bisectrix for blue, yellow and red light.

Collection: private collection

F. Krantz glass modelF. Krantz glass model

the glass model as seen along the crystallographic b-axis (left image) and perpendicular to this direction (image at the right).

F. Krantz glass model     
top view of the model with detail of the label