This is a beautiful Adenda-Dickson Knife from S. Illinois and it looks reddish purple in color and it so close to perfect. It is guaranteed authentic for life and is about 3 and 9/16th inches in length and is 1 and 7/8" in width. This point is very thin and less that 3/16 thick. I am no materials expert but I think it is a form of Rhyolite. I am not sure of the spelling on that or the material. IT stands out and is a super nice piece. I have hundred in it so see how much it is worth to you. I guarantee authenticity and will refund if you are not happy within a 15 day period of purchase. This material could be a quartz due to a quartz inclusion in the tip. You be the judge. Shipping is $5.95 including insurance. I am an AACA member so check out my other auctions and bid with confidence.