Well, I am burning some of the smaller splits of the mystery wood that people think is either locust or Siberian elm (the majority siding with locust), and I am actually getting blue flames around the logs that are sitting on a bed of coals. This stuff is slow burning, but it is really dense and throwing off some good heat. Was actually mesmerized by the blue flames tonight and spent a couple minutes watching them. Don't know if I have ever seen blue flames from wood, much less this blue.