Orchid was a catalog color from 1991 to 2005. Do these dates look familiar? Is it a coincidence that Amethyst was produced in those same years? No, Orchid is cased Amethyst. I think there is a pattern developing here. If there is no clear layer on the bottom of your Orchid water bottle, then it is not Orchid. If there is a clear layer on the bottom, it may still NOT be Orchid. That is a story for a later date.
Blog Update; November 22, 2013 A new formulation of Amethyst was introduced in 2012 and the cased version of this new Amethyst is still called Orchid.