Depends on the year. If it is a pre-1920 coin, it is sterling silver and worth about $11 in scrap silver if in circulated condition, if it is a 1920-1946 coin it is 50% silver and worth about $6 if in circulated condition. If it has been circulated and dates 1947 and later and isn't an error or anything, it might be worth a quarter or so as a curiosity. Uncirculated coins of course are worth more than the values quoted, but without knowing the specific year it is impossible to say what the coin might be worth.
The exchange rate is currently: 1 British Pound equals 1.52 US Dollar
The Halfcrown coin was a part of the long redundant predecimal British currency system, and no longer has an exchange rate with other currencies. The coin represented Two Shillings and Sixpence (or half of a Crown, or 30 old Pence). At the time of Britains conversion to decimal currency in 1971, the Halfcrown converted to 12.5 New Pence. A Halfcrown GBP in 1970 had the purchasing power of about $2.04 USD today. NOTE - This historical conversion is the result of many calculations and considerations by a purpose designed program. The resulting answer should only be regarded as an approximation based on current exchange rates.
Maybe one dollar to a collector.
1 US dollar is worth 0.689 pounds. 1 pound is worth $1.4327
The value of the pound today July 24, 2014 against the dollar is $1.70. This refers to the British pound in comparison to the US dollar.
As at 11Oct09 1 British Pound was worth 1.5820 US Dollars.
As of 31Dec90 GBP1 was worth USD1.9350 starting 1990 on 01Jan90 at 1.6060.
it does
One dollar.
a dollar
On 15-Jan-2010, one US Dollar was worth £0.61 (British Pounds), €0.69 (Euro) and ¥90.97 (Japanes Yen).
It is a British Penny and a US coin cut in half and stuck to each other. It has no value.