Okay, all this apparent controversy over Purpleheart has prompted me to get off my lazy a$$ and look the friggin info up. Here's what I found and is confirmed by several different sites.
""Purpleheart" is the trade name for about 20 different species of wood in the genus Peltogyne. Exotic Wood Group's Purpleheart belongs to the species paniculata. Purpleheart wood (regardless of the species) is very hard and dense, with an average specific gravity of about 0.86, and requires sharp tools for cutting.
Native to the tropical rainforests of Central and South America, Peltogyne paniculata trees grow to heights of about 100 to 150 feet, with trunk diameters reaching thicknesses of up to 5 feet..."
"Allergic reactions to Purpleheart dust can include skin irritation and/or nausea. Of course, as when working with any wood, adequate ventilation, as well as skin, eye, and breathing protection, are paramount. Although the heartwood is a dullish brown when freshly cut, it changes fairly rapidly to a vivid purple. Over time, with exposure to ultraviolet light, Purpleheart will inevitably darken to a brownish color. This process can be slowed, although not completely stopped. Ah, such is life. To prolong the length of time that the wood remains a lustrous purple, it's recommended to periodically apply a UV-resistant finish to the completed piece."
So there is the true origin of Purpleheart. I was misinformed about the Mahogany thing. I guess the only real way to tell if what I bought was "true" Purpleheart is the fact that the purple wood turned brown when I freshly cut/rasped it and then changed back to purple as the "true" species is want to do.