There's no "MD" mint mark on any US coin. The mint mark on a Peace dollar is near the word ONE on the back:
No mint mark = Philadelphia
D = Denver
S = San Francisco
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About $27.
A 1922-D Peace Dollar in very good condition (VG8) is worth: $20; if its mint state is MS60, its value increases to: $35.00
The 1922 Peace dollar is the most common of them all in any grade. Typical Mint State coins are in the $41.00-$55.00 range.
Please check your coin again. The Carson City Mint closed in 1893.
1922 is the most common year for Peace dollars, Mint State coins in the grade range of MS-60 to MS-63 are $22.00-$33.00 retail.
1922 silver dollar with closed eagle wings
About $27.
A 1922-D Peace Dollar in very good condition (VG8) is worth: $20; if its mint state is MS60, its value increases to: $35.00
The 1922 Peace dollar is very common. Circulated examples are $30.00-$36.00. Typical Mint State coins are $38.00-$43.00
The 1922 Peace dollar is the most common of them all in any grade. Typical Mint State coins are in the $41.00-$55.00 range.
If there's no mint mark, then it was minted in Philadelphia.
Please check your coin again. The Carson City Mint closed in 1893.
The 1922 silver dollar coin known as the Peace Dollar features the image of Liberty on the front and an eagle on the reverse, not Apollo. A 1922 Peace Dollar in average circulated condition can be worth around its silver melt value, which fluctuates with silver prices. In mint condition or rare varieties, it can be worth significantly more to collectors.
Assuming the coin is circulated, the 1922-D Peace dollar is a very common coin with retail values of $16.00-$22.00 depending on the grade of the coin.
A very common coin, circulated examples are $32.00-$37.00 Typical Mint State coins are $40.00-$43.00
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The mintmark is above the tail, below O of ONE