What is the first line of "A classic is forever"?

The first sentence of "A classic will last forever" is "A diamond will last forever."

"A diamond is forever, a diamond will last forever" is the classic advertising slogan of the diamond brand De Beers. This led to the subsequent phrase "A classic will last forever." In 1951, the then JWT Chicago began to create an image for De Beers, and "A Diamond is Forever" was a classic created at that time.

In 1951, JWT Chicago created De Beers' English tagline, "A diamond is forever," which translates directly to "A diamond is forever," and it's clear that this direct translation of the phrase sounds a bit empty. The direct translation of the phrase sounded a bit empty. So it was rumored that De Beers went on a nationwide search for a suitable translation;

After several months of selection, a university teacher's phrase "A diamond is forever" was finally chosen, and the Chinese slogan was eventually launched in Greater China.

Expanded Information

A simple advertising slogan perfectly summarizes the characteristics of diamonds: "Diamonds are forever," meaning eternal, and referring to their hardness and stable chemical properties. The composition of the diamond is a single carbon, carbon at room temperature chemical properties are not active, it is difficult to react with other substances, preservation of a longer period of time, even if the contact with some chemicals is also difficult to be damaged, corrosion and so on.

Diamond is the world's highest recognized hardness of the material, its Mohs hardness of 10, so some industries will use diamond to cut a variety of hard materials. Because of these characteristics, the diamond's "eternity" is perfectly interpreted.