How can you tell if glass is antique?

How can you tell if glass is antique?

Although many antique glass pieces are unmarked, there are a great number of pieces that do have glass markings....Other markings on antique glass pieces that offer clues to its age are:

1. Pontil mark of a blown glass piece and whether it is highly polished or not.
2. Mold marks.
3. Any marks within the glass itself such as bubbles.

Why does my glass have a seam?

Molded or pressed glass will not have a pontil mark on the bottom. Instead, look for seams present to indicate that a mold was used in the manufacture, as mentioned above. The mold seams are usually found on the sides of the piece where a mold would have fit together during production.

Can glass have a seam?

Most pressed glass has a seam, which is a thin line along an edge. The mold can produce various designs, patterns and even a pattern mimicking hand cut glass.

When did glass bottles have seams?

If the seam goes to the neck's top but stops before the lip, the bottle was likely produced from 1880 to 1910. However, entire bottle classes stand as exceptions to this rule. For example, mid- to late-19th century fruit jars and sheared top bottles have their own mold seam designs.

How can you tell if glass is worth money?

1:142:00How To Identify Valuable Glass by Dr. Lori - YouTubeYouTube

How can you tell if a glass is handblown?

How can you tell if a vase is hand blown?

1. Pontil Marks. A pontil mark, also called a pontil scar or a punt mark, is left on a piece of hand-blown glass when the glassblower removes the working rod or "pontil iron" from the glass object.
2. Slight Irregularities.
3. Air Bubbles.

Does handblown glass have seams?

Hand blown glass has some tell tell characteristics as well! You will not find a seam on these pieces, however you may find a “rod mark” at the underside of the piece from where it was removed from the rod it was created using.

How do I know if my glass bottles are worth money?

The Age of the Bottle While not all old bottles are valuable, an older bottle is more likely to be worth more than a newer one. Seams and pontil marks are two of the ways you can determine a bottle's age. The pontil mark is the mark at the bottom of the bottle where it was attached to the glass blower's pontil rod.

What are the dots on glass bottles?

What are the small dots on the bottom of a bottle for? The sequence of space and dots represent a mold code number and they allow electronic control of the production process and of that particular mold.

What makes antique glass different from modern glass?

Antique glass made from molds might contain grit, whereas modern glass does not. Some old glass also has an asymmetric shape from uneven cooling. Pressed or molded glass often has seams that show the edges of the mold. In early methods, glass molds were clamped together until some of the glass oozed out, leaving rough seams in the glass.

Where does the seam in a glass bottle come from?

Seam rises completely to the top of Bottle At the height of the industrial revolution, glass manufacturers quickly adapted mass production techniques -- instead of molding or shaping the whole bottle by hand in the open air, as was originally done. It was found that by blowing the molten glass into prepackaged molds greatly simplified the process.

How is the seam method used to date glass?

THE SEAM METHOD - OF DATING OF GLASS BOTTLES At one time almost all bottles were completely hand blown (in the open air) without the aid of molds of any kind. Such work required skilled craftsmen and a great deal of manufacturing time. Small wonder then that in many cases the bottle was more than half the cost of the product.

Where are the mold seams on pressed glass?

The mold seams are usually found on the sides of the piece where a mold would have fit together during production. Rough mold seams often indicate lesser quality glass, but that doesn't mean those pieces are not collectible.