Thanks to requester Heather for her picture (to the left) of a nice Iraqi riyal, or 200 fils, silver coin:
RIYAL: 0.3215 troy ounces silver
There are other coins with similar appearances. They are lower-denomination coins as shown on this page [PRESS HERE].
To figure value of the one riyal coin, start with the value due to silver content. This is called base value, or BV. Compute BV by multiplying the current price of silver (look it up at kitco.com, it changes every day) by 0.3215. For instance, if silver is selling at $15 US dollars per troy ounce, BV is 15 x 0.3215 = $4.80 US dollars.
The approximate catalog value of the 1 riyal coin is then:
worn: BV + $3 US dollars approximate catalog value
average circulated: BV + $16
well preserved: BV + $40
fully uncirculated: $400
Finding uncirculated pieces is almost impossible, which is why the 'fully uncirculated' price is sky-high.
Heather's coin in the picture is in average circulated condition with good eye appeal and no problems such as scratches, stains, spots, nicks, or gouges. It catalogs around $20 US dollars. These coins appear to be in demand currently. Heather could probably sell her coin on eBay near the $20 level, maybe even higher than $20.