The Devaluation of Huvishka's Coinage

Background: Early Innovations

The regions conquered by Kajula Kadphises and Vima Taktu had been divided amongst a number of rulers, and each was using their own weight standards and coin types. The Kushans issued regional types broadly conforming to these local types and weights. Vima Taktu initially followed this practice, issuing what MacDowell (1968) identified as three different 'regional types'. The northern, 'Bactrian' issue was in two denominations 12g and 1.5g; the middle, 'Gandharan' in 9-10g and 2g; and a southern, 'Indian', type struck to 4g. However, early in his reign the coinage was standardized and a single coinage was issued across the whole empire, with a new weight standard of about 8g.  

This was the first of a number of major reforms the Kushans made to their coinage. The next king Vima Kadphises introduced a gold coinage, and revised the weight standard of the copper. MacDowell argued that this new standard was struck to the old Attic standard current in Bactria under the Greek kings. For this reason he named the largest denomination the tetradrachm. The idea has some merit and the name has stuck, being the standard one used to refer to the Kushan copper coinage. This general pattern remained the same for the future Kushan kings, a gold and copper coinage being issued in parallel, each with its own weight standard.

Huvishka's Devaluation Huvishka continued the tradition begun under Vima Kadphises. However, at some point during his reign he substantially reduced the weight standard on which the copper coins were based. That this was a reduction in the weight of the old standard, rather than a new standard, is clear from the dies. The coins shrink slightly (from an ideal of about 3cm to about 2.5cm), but they continue to be struck with a die designed for the full weight coin, so that on any surviving Huvishka coin only part of the design is visible. Note, it is actually slightly inaccurate to call this reduction in weight a 'devaluation' because as explained below the effect was to over value the coin against its intrinsic worth.  MacDowell (1960) and Chattopadhyay (1967:206-8) disagree over the details of this devaluation. MacDowall believed that it started under Huvishka and proceeded in three stages, with a different reduction being implemented for each of the obverse types. Chattopadhyay proposed a different scheme (and slightly different standards at each stage). He believed that the devaluation actually began under Kanishka and that the dramatic devaluation as a single step. Vima Kanishka Huvishka Vasudeva MacDowell 17g 17g El. 10-12g 9-10g 15-16g Co 11g 6-10g Cu 8-9g 7-9g 8-9g Chattopadhyay 17g 15-16g 15-16g 11-12g 9-10g The difference in weights between the two should not be exaggerated, as the copper coins are often struck only loosely to the standard in force, and this combined with wear can make assessing the exact standard very difficult.

Huvishka Types Thecopper coinage of Huvishka are extremely varied. Khan (1996) lists over a dozen obverses and more than thirty reverses. However, it has been clear that all the types conform to a limited number of models.  The obverse has a legend (usually blundered or partially obscured) that reads: žAO žAONANO OOžKO KOžANO In the center, one of three designs is used. With the king seated on an elephant, or reclining on a couch (or throne), or seated cross-legged on a cushion. MacDowell originally speculated that these might be linked to regions but archaeological finds since have shown this cannot be the case. The reverse types has a standing figure of a god, with the gods name written to the right (and again often blundered). On the left there is a dynastic symbol, replaced by a barred version of the same symbol in later issues. A wide variety of gods are named, the most common being Athsho, Ardoksha, Mao, Miiro, Nana, Oesho, Oedo, Pharro, and Heracles.

An analysis of coin weights found in the northern regions of the Kushan Empire is informative. In Bactria, only the heaviest denomination (usually referred to as the tetradrachm) circulated in any significant number, and in Gandhara finds of the smaller denomination are still relatively rare. this means that a chart drawing on these regions provides a good indication of the weight of the largest denomination, the Tetradrachm. Though from Vasudeva onwards the problems are complicated by the difficulty of distinguishing the coins from their successors and imitators.

Weight

2g

3g

4g

5g

6g

7g

8g

9g

10g

11g

12g

13g

14g

15g

16g

17g

18g

Soter Megas

Vima Kadphises

Kanishka

Huvishka (Early)

Huvishka (Late)

Vasudeva (and imitations/successors)

Kanishka II (and imitations/successors)

The sample is based on the collections of Herat and Kandahar museums, and finds at Takhti-Sangin (MacDowall & Ibrahim, 1978, 1979; Zeymal 1997; Facena et. al. 1993; Rahman, 1970). The broad outline is clear (change of Weight standard under Wima, significant devaluation under Huvishka, and a further devaluation under Kanishka II). There are several problems. Firstly, the samples are relatively small, because these reports are not common. Secondly, even in these reports most coins are not pictured and the assignement of the coins for Vasudeva and later kings is difficult. This is particularly a problem for Huvishka types where their is rarely more information than 'early' or 'late'. This makes checking the details of MacDowall's or Chattopadhyay's scheme difficult.

Why are coins devalued?

It is an obvious question, why the Kushan king would devalue the coins. Ancient coins are not tokens, like modern currencies, they are made of precious metals (bronze, copper, gold, silver, etc) which are actually valuable in and of themselves. So while reducing the weight would allow more coins to be minted from the same amount of copper, it would not increase the value, as someone would still expect to be paid the same weight whatever number of coins that was. 

However, if the coins were fixed against some other valuable item then it would be possible to reduce the weight and still retain some of the coins value. The Kushans did this with their gold coinage. Each gold coin was worth a specific number of copper coins. The original purpose of this was probably simply to standardize the copper value in the cheapest possible way. The chart above shows that even tetradrachms struck to the same nominal standard could vary by several grams. Looking at the weights of gold coins (Mukherjee, 1978) is instructive. Of 61 coins weighed in the Indian Museum 57 fall between 7.5 and 8g, and most fall within a few tenths of a gram of the standard (which was about 7.9g). This is an incredibly tight standard compared to the copper coinage, and its purpose is no doubt to ensure that each gold dinara was worth the same amount. It probably also required considerable effort. Rather than in engaging in the same effort with the copper coins, the Kushans simply guaranteed an exchange rate against the gold, ensuring that all copper coins (despite the slight variation in weight) were of the same value.

MacDowall proposed that Huvishka exploited this by reducing the weight of his copper coinage, but retaining the guarantee against the gold coinage. He thus increased the value of his copper 50-70%. This would have allowed Huvishka to spend a far greater amount than he really had, an opportunity few rulers would be likely to overlook. 

It is important to realize that this is nothing like the debasement of Parthian silver in the first century, or the gradual adulteration of Kushan gold coins with silver. Both of those are lies, in which the minting authority tries to pass off a less valuable coin at a higher rate. In this case it was very obvious to everybody that the metal content had been devalued, but it retained a higher token value because it could be exchanged against the intrinsically valuable gold coinage. Attempts like this (to in effect create a token coinage) usually ended in disaster in antiquity, but not because there was a deliberate fraud being perpetrated.

The effect of devaluation

This was not a new practice, the emperor Nero had done something very similar with the Roman Silver coinage about a century before Huvishka (MacDowell, 1968 & 1992). So some of the effects of such a policy are well understood. 

The intended effect, for the Kushans, was to allow them to spend more money than they really had. That goal was what concerned the minting authority, and it is important to remember ancient governments did not care about economics the way modern governments do and their interest probably did not extend beyond that initial goal. However, the secondary effect was to place a coin in circulation which was worth more than its intrinsic copper value. Undoubtedly the public looked to exploit this for profit.

Firstly, they could forge the coins. If a coin is worth more than its intrinsic value turn copper into coins, and they can be exchange at a profit. The larger the devaluation, the greater the profit. Forgeries of Kushan coins were not uncommon in this period, but they give the subjective appearance of becoming far more common in the reign of Huvishka, and proliferating across the empire, and proliferating across the empire..