House historians now know who made the glass window panes at the mansion in San Jose... and it's not Tiffany, like some have said during tours.
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Historians say the windows were actually made by John Mallon, a glass artist in the late 1800's.
The Winchester Mystery House historian had a suspicion the windows were not made by Tiffany, but was only recently able to prove it.
During some restoration work at the house, workers found an envelope tucked inside a wall.
It contained a stamp for Mallon's business, the Pacific American Decorative Company.
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