Flour Mill/Grind Stones - Real Stone vs Ceramic Corundum / Carborundum (i.e. Sandpaper)? is Abrasive in our food SAFE?
I'm very much into wood working which involves some hand tool sharpening. In the sharpening world, we're very familiar with abrasives. Some people use sandpaper taped to a piece of plate glass or a flat granite tile working from course (say 400) to fine (say P2000 wet). Other people use a wet stone which is basically a block of adhesived together Aluminum Oxide (the main ingredient/abrasive in most sandpapers). Others (including me) prefer natural stones to sharpen with. I like them because they're VERY hard and don't wear out. The other methods use grit particles which wear away in a slurry of tool steel and abrasive particles/binder as the tool is sharpened. It's not a big deal because you wash the stone off when you're done.
That background given, I don't like the idea most grind stones are using when it comes to flour mills. I don't think most bakers think about it like I just did. But having used abrasives as much as I have (especially with stones and grinders) I don't like the idea of all that abrasive and binder going into my food/flour. I've also heard that dentists don't like the abrasive either (read that it can effect tooth enamel). Not to mention eating aluminum... I know... I know... they say it won't hurt but still... it's aluminum! Most home flour mill grinder manufacturers call it Ceramic Corundum but from what I've read (including the Wikipedia on "Corundum"), that's just another name for Aluminum Oxide. I've seen this in several places so I assume this to be the case. It makes sense, most stones for grinders (bench grinders for instance) are made using Aluminum Oxide as the abrasive.
But long and short of it, does this bother anybody else? I personally don't like the idea. I'd really like to find a real stone grinder if there is such a thing. Maybe it's not a big deal regarding our health but I'm curious.
The stones I use for sharpening tools (and my food knives) are Arkansas Oil Stones made by Hall's Pro Edge. I really have been happy with them. I use diamond for the course roughing out and switch to a black oil stone for the final edge. Works great! That's unrelated but part of what got me thinking about the stones in grinders.