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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 rigi...

A wholly general method is presented to produce accurate drawings of any crystal in any orientation from a stereogram of the crystal. A standard stereogram is prepared with all faces plotted, and the desired viewpoint is marked. The stereogram is then rotated as necessary to place this mark on the W radius of the net. The stereogram is then held in position, and the viewpoint moved along the W radius to the center of the net. Concurrently, all face poles are moved along their small circles by the same number of degrees and with the same sense of motion as the viewpoint. The poles are now reoriented. Next, appropriate zone circles and their diameters are drawn. Each zone has a zone pole whose direction on the stereogram is parallel to the edges in the zone. A line parallel to this zone pole, called an edge line, is drawn from the net into the adjoining drawing area. Edge lines are drawn for each zone of the crystal, and the crystal drawing is then made by drawing necessary edges to outline faces.