You've pretty well got it! But Catalina's statement about South Africa and the closed genepool is true. Their chinchillas were by and large stuck in a sort of time warp unaffected by the progress being made elsewhere in this colour/pattern of PERSIAN (its type standard reads exactly the same as a black for example, in just about every association) and those cats are homozygous silvers... I started breeding in 1964 with chinchillas and it was shocking to think of mating to anything but (black) chinchilla or black shaded silver!!!! (Of course, there are now also "contemporary type" chinchillas in SA.)

However, starting in the USA, matings to blacks, blues, etc, to improve type took over and now most of the world has chinchillas bred that way (back in the pedigree!)

The hard fact is that a chinchilla should ideally have the same type as a best in show black persian.
Lesley