Hobbies And Interests
Instructions
Hand-Blown Finishes
Look for seams running from the base toward the neck. Bottles that lack seams are hand-blown (sometimes called free blown) and are usually earlier than bottles with seams (made in molds). Hand-blown bottles usually date before 1860.
Look for evidence of blowpipe removal from hand-blown bottles. The blowpipe is located at the mouth of the bottle, and the lip and neck may show evidence of removal of the blowpipe. Early bottles often have rough, jagged and irregular lips that resulted from shearing or cracking-off the blowpipe.
Look for a smooth, glossy lip on a hand-blown bottle. This indicates that after blowpipe removal the lip was reheated and made smooth. This is called a fire-polished finish. Fire-polishing is most common on bottles made circa 1800 to 1860.
Examine the lip to see if it is flat and rough to the touch. This may indicate a ground finish where the rim was ground flat and uniform upon blowpipe removal. Ground finishes persisted into the early 1900s.
Look for an irregular band or collar applied to the lip. Glassblowers often applied a narrow band of extra glass around the lip (laid-on-ring) to aid in closure. Irregular laid-on-rings date before 1850, but molded laid-on-rings became common in the late 1800s.
Molded Finishes
Look for mold seams that disappear in the neck. The body and shoulder of these bottles were made in molds, but the finish was hand- or tool-applied. The finish will look uniform and standardized, and these bottles would likely date from circa 1870 to 1920.
Look for seams that extend nearly to but not all the way to the lip. The finish on these bottles may have been fire-polished and date slightly earlier than completely machine-made bottles.
Look for seams that extend all the way to the lip. These are bottles completely made in molds and date from the early 1900s to present.
Closures
Look for a simple open mouth to indicate a cork closure. Bottles sealed with corks are among the earliest and will exhibit simple open mouths.
Look for a thick, tapered collar just below the lip. This may indicate a bottle with a bail-type closure to hold the cork in place. Bail-type closures (although still used in modern times) probably date circa 1850-1900.
Look for screw-threads just below the lip. This will indicate a screw-thread cap and probably dates after 1920.
Look for a round bead around the lip. A beaded lip from a machine-made (molded) bottle usually indicates that it had a crown-cap, such as a modern beer bottle. Crown caps were patented in 1892.