google this Gory... Chalukyas of Gujarat see here for a quick low down... http://coinindia.com/fifty-coins3.html
The CoinIndia link mentions the progressive stylization of these in their paragraph #27. My page shows this a little more graphically. http://www.forumancientcoins.com/dougsmith/gadpaisa.html These are hard to beat when it comes to cheap old silver. The style got strange but the metal remained pretty consistent over a long period.