QUOTE(Drusus @ Nov 25 2007, 09:24 PM)

Its KM# 878 2-1/2 Rupees Afghanistan Silver .6632 ASW Minted during the kingdom of Amanullah 1919-1924. I think its 1922 which would make it worth about 8.50
Got it all there but the date

On the second thumbnail (the obverse) you start from the top of the coin being the star, followed down by the toughra (or monogram) of the ruler's name and title, followed next by the date. The date on Afghani coins are in persian, so we use the persian numerics reading left to right. The lunar Islamic Hijri calender is used for coins up through 1918. From 1919 on (with a few exceptions) the coins are dated using the solar Hijri calender. If using a Krause, the dates would be defined as "AH" for lunar Hijri and "SH" for solar Hijri. The year SH1300, as indicated on the coin, correlates to AD1921.
Generally, the Islamic Hijri calendar is based on a 354 day year as opposed to a 365 day year and is used in determining holy days. Wikipedia will bring up a rather in depth study of the Hijri. The Hijri was the emigration of Muhammad from Mecca to Medina, which occurred in AD622. But, since that was the first year of Hijri, we need to add the solar Hijri years (based on a solar calender of 365 days) to 621, instead of 622. Otherwise, SH1 would yield us AD623!

When you begin to study a coin, you will find there is a life's worth of knowledge to be gleaned from the historic, scientific, religious, economic, and political aspects of the coin in hand. Enjoy investigating further and welcome to the forum!