Wow, Tommy. What a neat coin. You have an old British crown from Charles (Carolus) the second, who reigned in Europe from 1660 to 1685. These old crowns are always valuable, especially when they are in good condition.
NEVER CLEAN A COIN. CLEANING RUINS VALUE.
Look at our picture of your coin. Most specimens are much more worn than this one. This picture comes from PetitionCrown.com, which is a tasteful and informative web site that deals with rare British coinage. Please click to their page about Charles II for more images and historical descriptions.
CoinQuest thanks PetitionCrown for use of their coin image. It is a beauty!
As to value, highly worn coins like this sell retail for around $100 US dollars or so. As condition improves, value goes up, as long as there are no problems with the coin, such as scratches, dents, stains, and cleanings. Use our Terminology page to understand the ins-and-outs of coin evaluation.
A coin like PetitionCrown's is in such wonderful condition that its value would climb to $1000 or more. Here are some approximate catalog values averaged over all the dates in the series:
6 PENCE (21 mm diameter)
worn: $65 US dollars approximate catalog value
average circulated: $475
well preserved: $1300
SHILLING (21 mm diameter)
worn: $100 US dollars approximate catalog value
average circulated: $800
well preserved: $2250
shillings dated 1666 are rare and catalog at $6500 average circulated, $13000 well preserved
shillings dated 1680 are rare and catalog at $2750 average circulated, $6500 well preserved
shillings dated 1681 are scarce and catalog at $1400 avg. circulated, $2600 well preserved
shillings dated 1682 are rare and catalog at $3250 avg. circulated, $7000+ well preserved
1/2 CROWN (33 mm diameter)
worn: $200 US dollars approximate catalog value
average circulated: $1300
well preserved: $3200
half crowns dated 1670 are more common in lower grades but less common in higher grades, and catalog at $100 when worn, but $4000 when fully uncirculated
CROWN (39 mm diameter)
worn: $175 US dollars approximate catalog value
average circulated: $725
well preserved: $4000
crowns dated 1669 are less common and catalog at $1300 average circulated, $7000 well preserved
I am concerned, Tommy, that you indicate 'little or no wear' for your coin. This is very exciting, because you might have a truly valuable piece. But it can be detrimental, because rare coins are often counterfeited. If you like, please use the Contact Us page to start and e-mail exchange with CoinQuest and we can discuss this further, especially if you have pictures of your coin. Alternately, seek out coin authentication services PCGS, NGC, ICG, or ANACS on the web. These people will authenticate your coin for a fee. Do not use other services.