Over the years hunting arrowheads from Wyoming to Oregon where obsidian is the main material used, I have found the vast majority of them to be thin. There is a fantastic artifact museum in Klamath Falls Oregon with thousands of points and most obsidian points are thin. Blades and tools are thicker. I have made several blades over the years and they are thick because they break easily when skeining or dressing if used to pry sidewise as often happens when field dressing large animals! Also used obsidian, agate, and jasper to hunt deer, elk, moose, and bear with good results and like a moderately thin point. Watcher