I think internal oils in the silicon based wood turns it purple while
a hot bandsaw or sun will dry (evaporate) the surface and turn brown.

Consider Coastal Redwood decks. Pinkish color until it gets boiled in the
sun - then it turns a silver gray. Sand off that surface and back in the pink.

Most wood changes color and gets hard in the sun.

I have purple heart tree elements (heavy) and sewing wall hanger.
I made some nice file handles out of it and white oak. It was a
diagonal layered design - looks like a candy cane of sorts - oiled it
and it is in my file drawer with the others. It is large as it holds
a 3/4" round wood rasp.

Martin

Ecnerwal wrote:
In article ,
(Doug Miller) wrote:

In article , "Leo Lichtman"
wrote:
"Leon" wrote: Vivid purple turned brown when turning and sanding a
pen..... what kind of
acid are you using to bring back the pruple?
^^^^^^^^^^^^^^^^^^^^^^^
Purple heart is brown when it's cut or turned, but the color returns to the
surface on exposure to air. Exposure of the purple surface to sunlight will
turn it to an ugly brown. So, after turning a pen, just wait, and don't
leave it in the window.
Not in my experience -- I've observed the purple to be *intensified* by
sunlight.

I've had PH bleach out brown (certainly seemed to be sun-exposure
related, though filtered through two sheets of glass and a coat of
finish), but I wouldn't call it an ugly brown - more like brittle,
tool-dulling black walnut - ie, pretty good looking, but not as nice to
work with as walnut. It's mostly "not purple" rather than "ugly", IMHO.
YHO may vary, or not be H. Last I looked the bag of shavings I tucked
away in the shed was still nice and purple.