How to Make an Accurate Three-Dimensional Model of Any Crystal from its Stereogram

Abstract

To make an accurate three-dimensional model of any crystal, plot partial stereograms of one face from each form on the crystal and all the faces with which it shares edges. Rotate each partial stereogram until the chosen pole is on the W radius of the stereonet. Translate the desired pole to the east along the W radius to the center of the net, moving all other poles congruently along the small circles of the stereonet. Label the reoriented poles. For any edge, draw a zone circle containing the poles of the chosen face and its edge neighbor, and the zone pole line. The orientation of this zone pole line is also that of the common edge of the two faces, so an edge orientation line may be drawn parallel to it. Then, draw this edge line on the stereogram at a convenient position and repeat for all edges of the face. Next, arrange the edges to make a face of chosen shape and size and repeat for all faces, keeping common edges constant in length. Finally, transfer multiple copies of each face drawing to a rigid material such as sheet balsa, cut them out, and glue the faces together with wood glue to make the model.