Large Coal-Burned Bowl & Water Purification

I made this large, coal-burned bowl to cook in using the rock boiling method. (Gotta give the "Primitive Technology" guy a shout-out. It was his videos that inspired me do mine similar to his.) Of course, it can also be used to boil anything including water for the purposes of purification in case your water source is questionable. Normally, you would make something smaller and purify water in smaller batches, but going this large leaves you free to do other things in a homesteading situation. Due to its size, it can also be used to collect rain water. The wood came from an injured tree - Atlantic white cedar - that I cut down using only hand tools. I split the log with my Tracker knife once it was more-less seasoned. I lost track on the number of coal changes, but the project took two and a half days to complete. I got better at getting the most out of a batch of coals as the work progressed. Once I burned through the dense inner core of the log, things started to go a lot faster. It was very important to scrape the charred wood between coal changes. Otherwise, low spots form that can get away from you in a real hurry if you are not paying attention. They must be filled in with sand (damp sand works better), so the rest of burn can catch up to these low-lying areas and keep the working surface flat. White cedar is not really prone to splitting as it dries, but apparently this was big enough. This left two cracks down one side of the bowl which ended up leaking. I am using pitch glue - a mixture of pine pitch and powdered charcoal - to seal them in. The seashell is held in place what is referred to as a survival vice. These things come in really handy and you can make them just about any size. Acknowledgement: As I said earlier, I owe a great deal of thanks to Dave the Australian "primitive technology" guy. I also need to mention Tom Brown, Jr., the founder of the Tracker School. I have taken a ton of classes at his school, and none of this would be possible without what I got there. Cavemen and primitive technology people of the world, unite!