That's an extremely broad question since there are thousands of coins that may be of interest, and not all collectors specialize in the same kinds of cois. You might start by getting a copy of either the Krause guide or the Whitman Red Book and reading through to see what's out there. You can also browse any number of web sites - see the links to the right for example.
Currently, there are coins for 1, 5, 10, and 25 cents for regular circulation. The half-dollar is produced in smaller numbers for the collector market only. The one dollar coin is also produced in small numbers, due to an overwhelming stockpile of earlier dates and general lack of use by the public.
7-23-11>>> Assuming the coin is circulated, the 1890 Indian Head cent is one of the more common dates of the series, with average values of $2.00-$5.00 for most coins. Values are a market average and only for coins in collectible condition, coins that are bent, corroded, scratched, used as jewelry or have been cleaned have far less value if any to a collector or dealer.
The 1852 & 1853 Type 1 Liberty Head gold dollars are high mintage dates of the series and considered common. Most coins have seen heavy use and show a lot of wear. In general retail values are $200.00-$300.00 but only for coins in collectible condition, coins that are bent, corroded, scratched, used as jewelry or have been cleaned have far less value if any to a collector or dealer.
7-24-11>>> Assuming the coin is circulated and has no "O" mintmark, the 1853 Liberty Seated quarter is one of the more common dates of the series, with average values of $25.00-$55.00 for most coins. Values are a market average and only for coins in collectible condition, coins that are bent, corroded, scratched, used as jewelry or have been cleaned have far less value if any to a collector or dealer.
This is one of the key dates of the Morganseries the value is higher than other Morgans even in lower circulated grades.And value to grade is very important.Please consult a trusted collector or dealer to get the coins grade.
It depends how much you have and what type of coins you have. Are they collector coins (as in, high grades, key dates, rare coins) or are they junk silver coins (as in, worn silver quarters from the 40s, silver dimes from the 50s, etc.). If they are collector coins, it is better to sell to a reputable dealer. If they are junk silver coins craigslist and eBay are your friends, but dealers and jewelery stores will usually buy them too. Don't go to places like "Cash 4 Gold" or other "Hotel Lobby" sellers. They will often times take 50% or more off the true value of your coins.
The Collector - 2012 I was released on: USA: 2012
Uncommon Valor - 1955 was released on: USA: 1955
Uncommon Knowledge - 1997 was released on: USA: 1997
If you're referring to their face value, it depends on the coins' dates. Quarters struck in 1965 and later weigh 5.67 gm, while silver quarters from '64 and earlier weigh 6.25 gm. There are 453.6 grams in a pound, so get out your calculator. If the coins are all from 1965 and later, almost all of them will be worth face value to a collector, so you can just turn them in at a bank. Don't use one of those "convenient" coin-counting machines because they charge 8% to 10% for that "convenience" If any of the coins are earlier, their silver content makes them worth at least $3 each at retail, so they should first be checked for any dates that have extra collector value, and the rest should be sold to a metal dealer. Here's a link to prices:
The Collector - 2008 I was released on: USA: 2008 (Chicago, Illinois)
The Uncommon Denominator - 2014 was released on: USA: 6 September 2014
Uncommon Clay - 1924 was released on: USA: 7 December 1924
Uncommon Threads - 2005 was released on: USA: 31 December 2005
Most old US silver coins were made of 90% silver and 10% copper (*) so at worst you'll get their current metal value from a scrap dealer, minus their profit of course. That varies depending on the current price of silver so you'll have to check a site that monitors prices. Of course, most of those "we buy old coins" places will take a heavy cut for their profit so you might be lucky to get 1/2 to 2/3 of their raw metal value. Also, depending on the coins' dates and conditions they might be worth a LOT more to a collector so selling them for scrap would be like selling a painting for its canvas. If any of the coins are earlier than the 1950s you should check out their collector values before selling.
The Insurance Collector - 1903 was released on: USA: September 1903
The Trophy Collector - 2011 was released on: USA: May 2011