Auctiva Emporium: CobaltMoon

Milk bottle time line This guide is a time line of how milk bottles were made to help give an approximate age of any milk bottle you find. Milk bottle collectors can be a great resource for information. Without help from a really great collector I could never of made this guide. Experience does make understanding milk bottles easer. In the bottle business technology was always changing. Some companies wear quicker to adapt and others slower. It could take ten years or more before the vast majority would adopt to a new technology. This is a general guide for many types of milk bottles. There are bottles that may be exceptions that don’t match this guide’s information. In bottle collecting there are exceptions to most rules. 1870's-1880's: First glass milk bottles were made. 1890's: The cap seat was invented, the ridge inside the lip to hold a cap. 1900: The paper cap is fast replacing the tin top and wire bail. 1903: The first machine made bottles were made. The seam goes to the top and a crude Owens Seal on the base of the bottle can be found up to about 1920. In the 20’s a new machine used a plunger that left a smaller, cleaner, more uniformed mark. A crude Owens seal is a good date clue. 1914-1916: last year of SCA purple tinted bottles. Manganese was added to glass to make glass clear. When this type of glass is exposed to radiation from the sun the glass turns purple over time. The more sun exposure or more manganese in the glass will make the glass turn darker purple. At the start of World War One our supply of Manganese was cut off and this beautiful glass could no longer be made. 1920's: Most milk was pasteurized due to laws. 1910-1940: Bottles may have been made with yellow straw tinted glass. You can general spot the color at the base of the milk bottle where the glass is thickest. 1920-1940: Bottles may have been made with light pink tinted glass. You can generally spot the color at the base of the milk bottle. 1934: First pyro-glaze painted label bottles were made. 1935: first short round quart bottle was made. 1940: first modern square bottle was made. 1940: The tall round embossed quarts start to disappear and being replaced by Pyro labels. 1940: The short round quart bottle was improved and starts to gain market share. The bottle required different equipment to fill and kept many dairies from using the shorter lighter bottles. 1950 Start seeing square milk bottles replacing round ones. 1960 The amber square bottle was used by some dairies to block out the suns harmful light. 1965 The wax carton is fast replacing the glass bottle. Wax Carton equipment was expensive and forced many small dairies to disappear or merge with larger diaries. There are still some dairies today that use glass milk bottles. Today’s milk bottles may have web addresses and dollar deposits but they are still being used. Final clues to dating a milk bottle. Most glass companies used a date code. These were commonly found on the base of the bottle or on the heel. Codes were important since milk bottles were reused the dairy needed to track the life of the bottle to evaluate the quality of the bottle. If a bottle has a number on the base lets say 23 and you think that the bottle was made in 1923. Use this guide to see if it possible that your bottle is from 1923. If the bottle is a tall round embossed bottle there is a good chance the bottle was made in 1923. If the bottle is a square pyro you know that the bottle could be made in 1923. Common sense and experience can help crack the numbers on the bottom of your bottles. Be careful, the numbers 48 and 52 appear on many bottles and are often not years made but are marks of who was the manufacture. Marks from important companies that made milk bottles. B : Buck glass Co Baltimore Md., 1909-1961. Buck made the first short round bottle and the first short square bottle. Climax De Laval L52 Lamb Glass Co., Mt. Vernon, Ohio, 1921-1964. Lamb glass contributed to the cream top design by using the baby face. In 1965 lamb was the third largest milk bottle maker in the country mTc: Thatcher Manufacturing Company, Elmira New York, Since 1900. When this company started they order bottles from Whitall Tatum and did not make any bottles even though the word Manufacturing was in there name. Thatcher did buy a number glass companies to make there own bottles over the years. I believe seals, with a K9, 1, and 48 are all Thatcher bottles, but I am not sure. Milk Bottle Glossary ABM: Automatic Bottle Machine first used in 1903 to automate the bottle making process. BIM: Blown in a mold Cap seat: Ridged or lip on the inside of the milk bottles lip to hold a cap. Cream Top: Bulb in the top of the bottle used to store cream. Cream tops came in many designs like the baby top and cop tops. Gill: Size 1/4 of a Pint. Owens Seal: A circle on the base caused by the manufacturing process. The older the bottle the more jagged and rough circle. Bottle made after 1920 has a smoother more uniform circle on the base. Pyro painted label: Pyroglaze enamel lettering fuse to the bottle for colorful labels. SCA: Sun Colored Amethyst. Glass with a purple tint changed from exposure from Slug plate: A slug plate is usually a circle or oval used for embossing. A slug plate allowed bottle manufacture to change embossing on a single bottle mold for many different dairies. Making a slug plate for a bottle is much cheaper than making a new mold for every bottle. TREHP: Tall round embossed half pint. TREP: Tall round embossed pint. TREQ: Tall round embossed quart.