Is this pot's surface safe for fermenting in?

[Angel]

Today a friend gave me an ornamental-looking pot with a lid which would be a good size for making sauerkraut in.

1) How do I know if its finish is a safe surface for fermenting in?
2) What do I look for when examining it? (if you can tell this way)
3) If I succeed in finding out which company made it, what do I need to know/ask them?

I think that it is ceramic- it is shiny and white on the inside whilst it has some colour and hand-painted pictures on the outside. It looks expensive and it was from an expensive shop.

I phoned the shop, however they no longer stock the brand or have records. I have also been unable to find it online.

Thank you,
Angel

[Christopher Weeks]

There is no great way to be sure, and there are a number of different things you might be considering when using "safe".

Many people prefer stoneware to earthenware. That just means that the clay-body has fully vitrified (turned to glass). You can test that with a bit of spit. Find a part of the bottom that isn't glazed -- maybe the whole bottom or maybe just around the foot. Put some spit on it and watch. If the spit is absorbed into the dry body, then it's earthenware and not stoneware. But some traditional fermentation processes specifically take place in earthenware, so that's maybe not something to be concerned about.

More worrying is the presence of dangerous metals in the glaze. Lead is the most famous of those but barium (at least) is also a problem. Both of those metals can be leached out in particular by acidic solutions (which our ferments usually are). I guess there are test kits available but I don't know anything about them really.

[Angel]

There is no great way to be sure, and there are a number of different things you might be considering when using "safe".

Many people prefer stoneware to earthenware. That just means that the clay-body has fully vitrified (turned to glass). You can test that with a bit of spit. Find a part of the bottom that isn't glazed -- maybe the whole bottom or maybe just around the foot. Put some spit on it and watch. If the spit is absorbed into the dry body, then it's earthenware and not stoneware. But some traditional fermentation processes specifically take place in earthenware, so that's maybe not something to be concerned about.

More worrying is the presence of dangerous metals in the glaze. Lead is the most famous of those but barium (at least) is also a problem. Both of those metals can be leached out in particular by acidic solutions (which our ferments usually are). I guess there are test kits available but I don't know anything about them really.

Thanks- I will look further into it then as I want to be sure that it's safe to use.