Thanks for all of the replies. To respond to some of what has been said I'll make these statements:
The skew is a Marples from Sheffield, England. I believe that it high speed steel. I've turned about 150 pens with it without problems.
I got the blanks from Ebay. They were not described as stabilized.
I wasn't scraping with the skew. Yes, I have been known to do that, but I wasn't at that time. I rough the black round with a 3/8 inch spindle gouge and then use a skew to shape the pen.
I've got 5 more pieces of this material, so I will have to see what happens with the next one. I had never read about Amboyna being hard to turn and I was shocked when I had trouble with it. I'm going to use something else for tomorrow's pens and see if I've lost my ability to turn pens.
Thanks again.