Slug plates allowed local businesses to emboss their own bottles.
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2012 American Digger Magazine Sampler ÂŽ
ends, the older the bottle. Unfortunately, this method is not accurate. Readers are encouraged to refer to this text’s age estimation chart for a visual reference of mold marks and associated bottle age. During the proliferation of mold-blown bottles, slug plates were developed. A slug plate is a reverse embossed metal plate that is inserted into a two or threepiece mold. This allowed smaller manufacturers and local businesses to emboss their own logo on a plate that would be interchanged in a standard bottle mold. The result would be individualized product branding without the expense of creating a unique mold. In the early 1900s, Michael Owens invented the automatic bottle machine. This invention revolutionized the industry. The 1903 version of his machine could produce 13,000 bottles per day. By 1909, improvements