Qing coin, need help with type

Got this coin, but I can't tell if it's the big or small Guang variant. N#12421

Hello

Small guang for me 

but seems to be a degenerate specimen (No Hartill number)

What exactly do you mean by 'degenerate specimen'?

These are coins of poor quality in the second half of the 18th century. To save money, mints were not as demanding as before on the quality of their coins. This is particularly the case for the Qianlong coins at the end of the century and the emperor had to react because the currency in circulation was becoming more and more dismal, but it is possible to find some degenerated coins before.

Thanks for the answer, Gros and Frenchlover.
How should I understand the term 'degenerate specimen'?
Does it refer to an unclassified type that hasn't been taken into account due to an unknown date and mint, or does it simply mean coins struck with a broken stamp?
And how to classify then mine coin, or it Hartill#22.597?

Mint is determined, degenerated means poor calligraphy, poor design.