These are part of the bottle collection at Ma’Cile’s Museum. They all used to be clear bottles, but apparently have turned purple due to sun exposure over the years. I was unaware that bottles could do this, but found this interesting snippet online:
Under UV radiation, the manganese combines with the oxides in the glass to create MnO2, a compound which absorbs light in the visible spectrum except that which creates the color purple. Therefore, as light passes through the glass, it appears purple.
FYI, glass manufacturers started using manganese in the 1860s, but mostly stopped by 1915 when they started using selenium. Both elements improved glass clarity.
The orange/gold bottles in the photo turned that color due to PhotoShop. :)