The whole process is done under a Microscope 5 to 8 times magnification takes up to 4 days but efective work maybee 3 Hours the rest is time to let the piece sit and the epoxie dry. Costs around 300 Dollars.

In Japan they often used grinded porcelain shards and mixed ist with Sodium silicate this is the best methode not even visibly under UV ligth and can stand high temperatures but the knowlege how to do it is mostly lost, and Epoxie is much cheaper and leads to the same result.

If I get access or buy an electric kiln in the near future per @webboy, I'll update how it turns out. 

Per the bubbling in the rest of the piece, I'm wondering if that's more enamel by an inexperienced hand during the repair process. Some self-attempting conservationists will go nuts with touch up paint on a damaged work when it just needed to be across one fine line. It looks like it was not really diluted during the application process. The color matching was OK at least but that's the only credit I'll give adherence to it. 

Since we're already in this hole of the vase, I have a couple tests I can try this weekend and see what comes out of it. 

@julia and @shinigami always appreciate the help with pinpointing its history a bit. 

It looks like it might be one of those Canton Violet (? sorry, I've forgotten already what this is called and it was only on here a few weeks ago), they can be painted rather badly. I agree with Birgit's dating and view on the lack of desirability, but I am not sure if you can send it back. It will depend ....