It can be very difficult to work out if a piece of jewelry is plated or solid gold. Gold Electroplating is almost undetectable to an untrained eye. It was a tradition in Egypt to plate jewelry in high carat gold to protect the jewelry, it was applied for practical reasons, that also look very good.
You can get digital gold testing equipment that can read if the metal is gold or gold plated. I have one, and it has saved me more money than what it cost many times over.
Alternatively, your local jewelry can test the metal. Also, if you have a jeweler's loupe, or strong magnifying glass, examine the wear points, the parts of the jewelry that receive the most wear and tear, if it is a secondary piece that is, you may be able to detect the gold plating, any signs of flaking, or peeling or a wearing away of the gold will tell you, it's more than likely, gold plated.
The price you paid, if it wasn't handed down, could also be clue, if the price was to good to be true, it probably, well, you know what they say....
