Solarized architectural glass

[1] However, solarized glass does occasionally appear in architectural contexts and uses, especially window panes, doorknobs, and pavement lights.

Since ancient times, one of the most common chemical decolorizers has been manganese dioxide (MnO2), which in small quantities, is an effective additive to produce clear glass.

[2] However, in large quantities, glass treated with manganese dioxide photo-oxidizes when exposed to ultra-violet sunlight over a period of years to decades.

In large quantities, these chemicals have turned glass yellow and amber respectively when exposed to ultra-violet light.

Most notably, many early 19th century houses in the neighborhood of Beacon Hill, Boston, MA have windows with purple panes of glass.

[2] This means that panes of solarized glass will turn a darker purple if they receive heavy exposure to light, such as on the south facing façade of a building.