LCS Find: South East Refining Bar

I haven't been buying much lately, but I'm still grabbing interesting old pieces when I can. I know this isn't my first of this kind of bar, but I'd have to consult the archives to see how many I have. But i do know for sure that my others don't have a serial this cool.

I'm not going to tell you when this bar was minted, or how many were made, or how much they go for in the open market. My understanding is that presenting available factual information without a source can get you downvoted into obscurity, so I'll just stick to what can be gleaned from the pictures I took of this bar and you can Google for specifics if you're interested.

Here's the back.