A 1926 uncirculated Buffalo nickel with the S mint mark fetched about $330 in 1975. Today that nickel would cost you more than $6,000, which is about a 9 percent compounded return over the past 37 years. These are common coin examples, and you can find better and many more examples perusing The Official Red Book. This annually published reference book lists the value of nearly every U.S. coin, U.S. commemorative, U.S. territorial issue, Colonial coin, post-Colonial coin and state-issued coin. And there are always a couple of coin dealers in big cities that can help investors assemble a collection of rare coins at acceptable markups.
Meanwhile, I have several of each of those coins above and other rare pieces that I separated from pocket change when I began collecting coins more than 60 years ago. Unfortunately, they're not uncirculated.
However, they have also appreciated enormously in value during the past 60 years. There are several reputable coin dealers in Rochester than can guide you.
Please address your financial questions to Malcolm Berko, P.O. Box 8303, Largo, FL 33775, or email him at firstname.lastname@example.org.