Vintage Cobalt Blue 'Milk of Magnesia' Glass Bottle

This is an antique to vintage medicinal glass bottle crafted in a vibrant, deep cobalt blue glass. It features a rectangular body with rounded shoulders and a short, narrow neck ending in a threaded lip finish. The front of the bottle displays highly detailed embossed lettering and graphics including 'MILK OF MAGNESIA' in an arched font, surrounding a central circular trade mark emblem with a shield and the signature 'C.H.P.' monogram. Below the emblem, it identifies the manufacturer as 'THE CHAS. H. PHILLIPS CHEMICAL CO.' located in 'GLENBROOK, CONN.' The construction suggests a machine-made process common in the early 20th century, likely dating between 1910 and 1930. The glass shows significant surface wear, including 'bloom' or sickness (cloudiness) likely caused by mineral deposits or environmental exposure if excavated. There are visible scuffs, light scratches, and dirt accumulation around the base and neck. The threaded top exhibits some oxidation and residue, suggesting the original metal cap may have deteriorated or been removed. Despite the surface weathering, the embossed details remain sharp and legible, showcasing the classic typography of the period.

Based on my examination of the digital images and description provided, I have assessed this cobalt blue 'Milk of Magnesia' bottle. The piece is an authentic example of a machine-made medicinal bottle produced by The Chas. H. Phillips Chemical Co., likely dating between 1915 and 1930. The vibrant cobalt hue remains the primary appeal for collectors. However, the condition significantly impacts the market value; the presence of 'bloom' or glass sickness—a chemical alteration of the glass surface—is permanent and detracts from the clarity and aesthetic appeal. The scuffs and residue suggest this was a 'dug' bottle rather than a well-preserved cabinet piece. Market conditions for mass-produced apothecary glass are currently saturated. While cobalt glass is consistently popular, this specific Phillips bottle was manufactured in the millions, making it a common find. Comparables for specimens with surface oxidation and 'sickness' typically realize prices at the lower end of the spectrum, whereas pristine, cleaned, or labeled examples command a premium. To fully authenticate this item and refine this valuation, an in-person inspection would be required to rule out modern reproductions (though unlikely for this specific model) and to check for hairline fractures or 'flea bites' on the threaded lip which are not visible in images. Scientific testing for glass composition isn't necessary given the low value, but provenance—such as recovery from a documented historic site—could add minor contextual interest.