1. Coins are struck, not printed. Paper money is printed.
2. There is no such coin as a "dime penny". There are dimes and there are pennies.
That done, if your "coin" has one side that looks like a dime and one that looks like a penny, it's a novelty item made by cutting apart 2 coins, swapping sides, and joining the 2 halves. It's worth the same as all those double-head and double-tail novelty coins that occasionally slip into circulation - a few bucks at a hobby or magic shop, but no interest to coin collectors.
In value, a penny is smaller. In size, a dime is smaller.
The value to a collector depends on the coin's condition. Show it to a coin dealer.
The dime has a greater value in trade, and greater purchasing power, but the coin is physically smaller than the penny.
If this is a penny struck on a dime planchet, it's worth about $150 If this is a dime that was restruck with penniy dies, so details of both strikes show, it's worth about $500 If this is a dime that somebody smashed a penny into, leaving an impression, it has no added value. Proper authentication is required.
dime
In value, a penny is smaller. In size, a dime is smaller.
It depends on what the error is and how dramatic it is. Without knowing what the error is it is impossible to answer without that information.
The value to a collector depends on the coin's condition. Show it to a coin dealer.
The dime has a greater value in trade, and greater purchasing power, but the coin is physically smaller than the penny.
If this is a penny struck on a dime planchet, it's worth about $150 If this is a dime that was restruck with penniy dies, so details of both strikes show, it's worth about $500 If this is a dime that somebody smashed a penny into, leaving an impression, it has no added value. Proper authentication is required.
No pH value, cf related questions on pH of dime-quarter-penny
Lincoln is on the penny, Roosevelt is on the dime. It's likely a novelty coin with no value.
As of 2014 the estimated value of a 1988 P dime in the U.S. is 22 cents. The value of coins does fluctuate by demand and the market.
Chances are, if it is the same size or looks like a dime, it may be counterfeit.
In average condition, about a dime.
The dime couldn't have been printed as a penny. Different productions and not connected during the minting process. Sounds like your coin is a damaged one.
dime