It would depend on the type and condition. I've seen Coronation coins/medals going anywhere from a few dollars to a few thousand.
Which King George? There have been six of them. The condition which they are in also makes a huge difference to their value.
Which coin
The 1911 US Barber dime is a common coin. A coin in average condition is $2.00-$5.00
The 1911 US Barber dime is a common coin. A coin in average condition is $2.00-$5.00
20.00
No, it is not a Five Pound coin. There were four different gold coin issued in 1911 with George V on the obverse and St George and the Dragon on the reverse. The Five Pound and Two Pound, both as Proof only, and the Sovereign and Half-Sovereign. The Five Pound coin was the largest of the gold coins in 1911 at about 38mm. The Half-Sovereign was the smallest of the gold coins in 1911 at 19.5mm. I cannot find any reference to a 1911 British 16mm gold coin.
Assuming it's circulated and has no mintmark, the 1911 US Barber dime is a common coin. A coin in average condition is $3.00-$5.00.
The Royal Mint did not produce any Crown (Five Shilling) coins from 1903 to 1926 inclusive, Proof, pattern or otherwise. It is quite unusual that no 1911 Crown was produced since it was the Coronation year of George V. All British "silver" coins minted prior to 1920 contained 92.5% silver. There was a silver Proof FDC Halfcrown coin minted in 1911.
It is a medal, not a coin and they are worth $30 - $35.
The coin has .12094oz of pure gold, the coin is worth $165.40 just for the gold.
See the related question below.
It has a value of about $30