This is a beautiful find out of Argentina, featuring true pink amethyst crystals from the Choique Mine. It occurs in geodic formations or cavities lined with crystals. The crystals in this one have a lot of sparkle to them.
The material has been analyzed at the California Institute of Technology and was described as "purplish pink amethystine quartz additionally coloured by microscopic hematite particles. They are not rose quartz
or pink quartz as classically defined".
So, it's formed by the same same processes that give amethyst it's purple color, but by definition amethyst is purple not pink. So, we are left with a conundrum of what to call it, but since the majority of people seem to be calling it "pink amethyst" we will stick with that label.