Believe what you see?

I had a telephone voicemail message this morning. Naturally, the caller had a question.

I immediately thought of a movie comedy where a slick con man is caught in the act and he asks the discoverer, "Who are you going to believe? Me or your own eyes?

It is funny. But this phone call proves that sometimes people choose not to believe their own eyes.

The caller said that he had a 1975-D cent that appears to be made of aluminum. He then said it weighed 3.1 grams, which is the correct weight for the 95 percent copper, 5 percent zinc alloy used for circulating cents of the time.

What does this mean?

It means the caller has the answer to his own question. The coin cannot be aluminum if it weighs what the mostly copper alloy weighs. Aluminum is much lighter.

However, I imagine headlines proclaiming the $250,000 projected value of the first aluminum cent to go up for auction in April are dancing in the caller's head.

After all, the color looks like aluminum, so why couldn't it be aluminum?

I will return the call and say that the cent is not aluminum. It might be coated with Mercury. That can change the color. It used to be done to mislead people into thinking they were getting a dime in change in a petty crime sort of way.

The color might be due to some other cause. I cannot say for sure.

One other factor that seemed to give the caller hope was someone else seems to have scraped the surface of the coin, but the scrape did not reveal a copper color beneath.

So with that faint hope, a telephone call was placed to me.

So I guess that puts me in the position of asking the caller, "Who are you going to believe? Me or your own eyes?"

Buzz blogger Dave Harper is winner of the 2013 Numismatic Literary Guild Award for Best Blog and is editor of the weekly newspaper "Numismatic News."