Half dollar 1925

[Le Numismate]

J'ai acheté ce jour un lot de pieces argent.
Parmis elles, il y avait une HALF DOLLAR de 1925.
C'est une commemorative de la STONE MOUNTAIN.

Elle est en argent 900/1000 pour un poid similaire à celui d'une 5frs semeuse.

Mais je me demande si elle n'aurait pas une valeur numismatique plus importante que sa valeur argent...
Je trouve des infos contradictoires sur le web.

Est ce que parmis vous quelqu'un connait la cote de cette monnaie, ou est ce que l'un ou l'une d'entre vous possede un ''Gadoury des States''?

Merci.

[silversteur]

Cotations 2010 :
STONE MOUNTAIN MEMORIAL. KM# 157 Designer: Gutzon Borglum.
1,314,709 exemplaires
70.00$ en AU-50
77$ en MS-60
85$ en MS-63
90 en MS-64
285 en MS-65

Je n'ai pas de cotation pour les états inférieurs.

[Le Numismate]

MS50 correspond à un TB en cotation française? Est ce bien cela?

[silversteur]

Non MS50 ca n'existe pas, la première cotation est pour AU-50 (Almost Uncirculated).

Mint State (Unc) - Absolutely no trace of wear.

Mint state coins vary from MS-60 to MS-70. As I stated earlier, MS-70 is perfect. No blemishes, good strike, great color, and a lot of other really nit picky stuff. Trust me, any coin you have that isn't slabbed isn't MS-70. It's like winning the lottery, twice. An average shiny new penny from the supermarket is MS-63. A really pretty one with no easily visible marks is MS-65. If you have an average roll of new cents from the supermarket, 2-5 will be MS-60, 5-15 will be MS-61, 25-40 will be MS-63, 5-8 will be MS-64 and 1-2 will be MS-65. If you are exceptionally lucky, one will be MS-66. An MS-68 coin is one in 100,000!

Distinguishing the difference between these uncirculated grades is where most of the black magic in coin grading is. Even with years of experience, coin dealers will disagree about these grades. Even the professional grading services aren't 100% consistent within these grade levels. Some coins are very difficult case studies. European coin collectors think that this American system of grading uncirculated coins is just downright crazy.

Almost Uncirculated (AU) - Small trace of wear visible on the highest points

AU coins come in AU-50, AU-55 and AU-58. As a novice, you probably won't be able to tell the difference between AU and Unc coins. I know I have trouble a lot of the time. The most important thing in grading an AU coin is to know is where the high points are on a particular coin so that you can look for the minimal wear there. Practice by taking a new coin from the bank, rub it back and forth on your mouse pad vigorously a few times, and see if you can see the wear. Hold the coin nearly sideways in a bright light so that the light reflects at a low angle off the coin. Look for a difference in how the light reflects from most of the coin versus the very highest points. If it doesn't reflect off of the high points the same way as it does from the rest of the coin, then you probably have an AU coin. Note that most AU-58 coins look much better than most MS-60 coins. One of the weird things about coins is that an ugly uncirculated coin often sells for more than a beautiful coin with barely perceptible wear.