How long typically do the commemorative coins from the US Mint remain on sale before selling out? For example the Infantry and Star Spangled Banner silver dollars from this year as compared to years past. Thanks in advance.
In reality, very few modern commemoratives ever sell out. Those that come to mind are the 2001 Buffalo, the 2006 Franklin, 2009 Lincoln and 2010 Boy Scout. Of those, the 2001 Buffalo has done very well, the 2009 Lincoln is still above water, the Boy Scout and Franklins have been pretty disappointing. If the 2012s do not sell out (and they most likely won't), they will be on sale until the end of the year. If you want either of the 2012 issues, you would probably be better off to wait and buy them in the secondary market, as you will likely get them at a better price. The primary reason for a commemorative's coming into being from the perspective of Congress and the Mint is it will generate funds for some purpose. For example, at least 20% of the price of the Star-Spangled Banner silver coins will be skimmed off of the top and will go towards War of 1812 celebration-related items in Maryland this year. Theoretically, then, that 20% (and then some more probably) will work its way off of the value of the coin eventually in the secondary market. In the majority of cases, then, it is better to wait to purchase the coin.
Modern Commemorative's in my opinion are more for the collector and not for the investor. Buy it because you like it, don't expect to make money from them any time soon. They'll likely be worth a whole lot more when you're long gone in the ground or cremated.