
I believe this is S. 306, H. 10.28 Zao Bian Wu Zhu. The Hartill listing mentions some of these were cast this way but this looks trimmed to my inexpert eye. Does anyone know how they were trimmed and how much was lost between this and the matching H. 10.27?
Are they found in stacks threaded together with both halves or separated? When were these issued? Did they circulate at par with 'normal' coins? This seems like quite a bit of work for value received.
Can someone suggest a good book on Chinese cash that is not primarily a catalog but discusses the how and why of issues rather than just assigning a number and adding occasional notes?