A friend has a piece of it and,yes, it does stay purple. But it might get washed out if exposed to sun every day, so you might want to avoid using it in any application where it gets direct sun every day.

I have been using PH as an accent wood for years. When cut/sanded, it turns brown. To regain the purple color, simply expose the wood to sunlight. But, if the piece has several different sides, you must expose all the sides to the sun equally. If a section gets shaded, there will be two different shades of purple.

I have made several picture frames with PH or having PH as an accent wood. I use water based poly as a finish to allow the purple color to remain natural(oil based finishes impart an amber tone that does not look good with PH) Over time---several years, the color fades a bit---but exposing equally to the sun for an hour or so brings the color back.

theres a line of ployurethanes minwax has called "polycryllic" polycrillic is the only urethane i know of that does not amber over time. almost all urethanes amber, including water based ones. just thought id mention it