Bottle Lips You can determine the approximate age of an old bottle just based on its lip. After the glassblower removed the bottle from the mold, he affixed a hot glass lip to the bottles neck. Next, he crafted the applied lip into the correct shape.

What is a Pontil mark on a bottle?

The pontil, or punty, is a solid metal rod that is usually tipped with a wad of hot glass, then applied to the base of a vessel to hold it during manufacture. It often leaves an irregular or ring-shaped scar on the base when removed. This is called the “pontil mark.”