Sometimes true … sometimes not true. I have made and lost money on coins. When I was a dealer, I almost always made money. It’s harder to make money as a collector because you don’t have as many sales outlets, and they are almost always dealers. Some dealers have the attitude that they pay less to the public, even if they need the coin. I found that silly. If it was something I knew could sell fairly quickly, I paid the collector a fair price.
Sorry, but no. One would wear it only if one were not concerned about having someone follow you home. Years ago, I remember seeing an old guy with tie clip that read, "I collect coins." Sorry, but I'd have to leave that one in my jewelry box.
The big concern that coin dealers (and collectors should have) have is to be followed home and robbed. The longest trek I heard was when crooks followed a dealer from Florida to his home in Nebraska. When he got home they called him on his home phone. When he went into the house, they stole his merchandise out of his car. The story was they were Russian mafia. The cops got most of it back because it was early copper which was not easy "to fence."
