Gail,
I have always been told that for sturdy things, like furniture, an object must be 100 years old or older to be considered an antique and breakable things like glassware and china must be at least 50 years old. I guess it depends on the country. We bought many antiques when we lived in China. When we were ready to move home again, the Government sent someone from the Antiquities Bureau to come to our home and evaluate all of our antique purchases. Each piece received a red wax stamp and had to be less than 200 years old to leave the country. I imagine that was to protect their heritage and make sure that Ming vases or Tang horses were not leaving the country. We had no problems as nothing was that old! The rules for antique boats and cars are different. They become "Classic" before becoming antique, but I don't remember the ages.
Maybe there is a quilter who is an antique dealer who would have better information. Wendy