In each issue this year, we're highlighting one artifact from the Texas Parks and Wildlife Department's historical collections.

This little pharmaceutical bottle was recovered from Bonham State Park. While the color may be the most eye-catching thing about it, this bottle was not always purple. Between 1890 and 1920, manganese was used as a clearing agent in the manufacture of colorless glass. When the glass is exposed to sunlight, a chemical reaction occurs which “solarizes” the glass and turns it purple. While finding purple glass does not necessarily indicate an archeological site was occupied during the late 19th to early 20th centuries, it does suggest that the glass was manufactured during that time. Between 1915 and 1920, manganese became difficult to obtain, and available supplies were used for the manufacture of steel during World War I.

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