Problematic Cash Coin

Here's a cash coin ostensibly from the Hsien Feng (Xianfeng) reign of Wen Tsung. This was a very turbulent, even chaotic, time in the history of the Qing dynasty, and perhaps that could at least partly account for the low quality of this example. It's both incompletely cast (note the multiple cavities) and exhibits a sprue that hasn't been taken down even with the rim (of course, if this was a "reject", then I suppose there'd be no reason to file that off as was the normal practice; on the other hand, you might expect that a "reject" would've been recycled and not survived). The markings on the reverse are nearly unreadable, and it looks as if there might've been a crack in the mold. On top of everything else, at a bit under 22 mm in diameter it's also rather undersized vis-à-vis the traditional cash coin.