Years ago I had a friend that made knives . Was out visiting one day and he came out with a display box with eight glass spears of different colors , six or seven inches in length . As with yours they looked like a real relic only glass . Would love to see how you chip them out . Never thought to do a search on Google , might be someone on there with a video . I have been making wood knives lately , I know I have messed up at least seven or eight blades . As you say , just work it a little bit more , and at the last stroke you mess it up .