white elephant

yes it is...
http://www.answers.com/white+elephant&r=67

Usually "antiques" is not used in the same sentence as "white elephant."

A "white elephant" item is usually an outrageous, totally useless knick-knac that needs to be thrown away or given to someone else, just to get rid of it. Those items are often the butt of jokes at the office gift-giving party.

An antique is at least 100 years old, and garners a little respect - just for surviving that!

A white elephant is not only a gift you don't want, you are expected to display it to avoid hurting the giver's feelings. Now, the original White Elephant was a real elephant. You not only had to treat it well, you had to feed it.

Hi Roger

I want to know whether you agree with Sullyfish, who replied to my question. You add some information, but is the usage of my sentence correct?

Many thanks.

It looks gramatically correct to me. Whether an antique would be a white elephant, depends on whether the giver's feelings are going to be hurt if you don't display it.

(i don't think that's necessarily true)