Proto-Currency of the Xiongnu by 𐰉𐰆𐰺𐰴𐰲𐰋𐰲𐰃

[Istinpolin]

Dear Friends,

I present to you 3 new pieces of proto-currency of the central Asian Tengrists the Xiongnu. I am really happy to have those

The article on those is here
https://www.academia.edu/36590074/New_examples_of_currency_of_the_Xiongnu_Empire_used_in_the_later_stages_of_the_Xiongnu_Empire

Zeno # 203128
https://www.zeno.ru/showphoto.php?photo=203128&cat=all&ppuser=268
Xiongnu/Hsiung -nu (The Great Hun Empire), AE Double Ring Object, 209 BC - 216 AD
produced around Mongolia/Northern China regions 
Weight: 66.56 gr; Diameter: 51.79x81.75 mm, Thickness: 4 mm.
Obverse: 2 compartments of rings attached, each comprising of two concentric circles (external and internal), which are connected by 4 radii. Grooved surface and edges.
Reverse: Uniface cast.
Reference: Zeno # 203128

Zeno # 203305
https://www.zeno.ru/showphoto.php?photo=203305&cat=all&ppuser=268
Xiongnu/Hsiung -nu (The Great Hun Empire), AE Multiple Rings Object, 209 BC - 216 AD
produced around Mongolia/Northern China regions.
Weight: 83.61 gr; Diameter: 32x160.5 mm, thickness: 4 mm.
Obverse: One large ring attached on 6 smaller rings ending in one more ring which is slightly larger and elongated forming a string of rings 160 mm long and 83 gr heavy. Grooved surface andedge.
Reverse: Uniface cast.
Reference: Zeno # 203305

Zeno # 203149
https://www.zeno.ru/showphoto.php?photo=203149&cat=all&ppuser=268
Xiongnu/Hsiung -nu (The Great Hun Empire), AE Plaque, 209 BC - 216 AD
produced around Mongolia/Northern China regions.
Weight: 45.42 gr; Diameter: 51x66 mm
Obverse: 4 holes across on top below 3 short holed lines below 2 long holed lines below 3 short holed lines below 4 holes across.
Reverse: Uniface, 4 control markes on bottom.
Reference: Zeno # 203149

I hope you like them.

Best wishes,
Burak

[Callimachus]

Forgive my ignorance here.

How have these items been established as being currency?  

The link you provided is quite interesting, but is rather vague about these items being currency. Quotes from this link:

Note: Most likely the item is a charm and possibly could have been used as currency also.
Note: Decorative or fitting item most likely for horses, use as currency or item for trade.
Note: Possibly a copper plaque . . . Might have been used as currency . . .

[JBF]

I kind of think "proto-currency" and "might have been used as currency" are sort of the same thing.  (how's that for certainty, "kind of," "sort of" ).  But, metal work has long been an item of exchange, such as tripods, cauldrons, striking god figurines in pre-coinage Archaic Greece.  So I think that that Istinpolin is correct, these items could have been used for exchange and wealth-holding, and therefore should qualify for "proto-currency."

But, in order to be proto-currency, it would have to be 'before' currency [causally (proto-), not necessarily temporally (pre-)],
when do the huns introduce coinage?