A set of Purple Heart key touches to replace the pearls on my friend’s sousaphone. I had a pen blank that I had rounded a while ago that was a near perfect fit but unfortunately the look of the end grain on purple heart makes for a less attractive piece and it takes a stain/polish terribly (in my experience). It looks brown and the grain distracts from the wood pretty severely so I will have to buy more pen blanks and use hole saws on the side of the wood to orient the more brilliant part of the wood outwards for display.
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Update.
After experimenting with dye and a vaccuum chamber I was able to get a very nice finish that did not outdo the original look of the purple heart by very much, it only seemed to enhance the existing purple in a believable way and made for a beautiful finished product.