What Do Colors and Shapes Represent in Stereographic Projections?

[scott_alexsk]

Hello,

Can anyone tell me what the triangles, squares, and ovals mean in the projection on page 19? Does this have something to do with the directions for the third axis? On the next page several of the symbols are black. What significance does this have, also?

Thanks
-scott

"[PLAIN 19"]http://neon.mems.cmu.edu/rollett/27750/L19A_Single_Xtal_Aniso1_3Apr06.ppt#317,19,Slide 19[/URL]

 

[Dr Transport]

They indicate symmetries of the lattice, ie a square is a 4-fold rotation, triangle a 3-fold rotation etc...