Why does the US Postal Service use costly materials to make stamps

Understanding Metered Mail for Your Business

US postage stamp and shipping prices go up Sunday - Good Morning America

What is the process for selecting images for US postal stamps? - Quora

Why does the post office create new stamps at a cost of $3,000 a

How valuable are Postal Commemorative Society gold stamps? - Quora

What is the value of first day covers and envelopes with U.S. stamps on them to collectors? - Quora

Postage Prices Just Went Up Again. Here's How Much Stamps Cost Now - CNET

US Postal Service announces new prices and services for 2013 > U.S. Air Forces in Europe & Air Forces Africa > Article Display

Can you reuse a stamp? If not, how does the postal service know if