Robert Bolton and other artisans working with Stained Glass Express are bringing Lithgow Library’s 120-year-old stained-glass windows back to their former, full-color selves inch by painstaking, dirty, leaded inch.

At first glance, the gleaming windows Bolton has completed so far in a Manchester studio almost don’t seem to be from the same batch of dark and dirty ones he has yet to start working on. And though each window had, on average, 20 pieces of broken glass among its 300 to 400 individual pieces, almost all the finished windows will still contain their original glass, held in place with all-new lead, when the restoration work is complete.

The goal is to restore the artwork and colors of the 32 windows, while keeping them as original as possible. Bolton clearly holds the original windows in high regard.

“The windows are spectacular,” he said as he described the process of disassembling the windows, repairing the glass where needed, cleaning the glass and then reassembling the windows with new lead outlining the intricate glass details. “They just need some attention. It’s fun to be able to look at these things as they come back to their restored youth.”

Bolton is the lead restoration artisan on the project to clean and restore the windows, which will be reinstalled as part of the larger project to renovate and expand Augusta’s public library.

Bolton said each of the windows, most of them about the size of a large serving tray, so far has typically taken between 120 and 160 hours to restore.

He ticked off tools and materials to clean unpainted stained glass: “Toothbrushes, water, a small amount of Simple Green (diluted), patience and elbow grease.”

“It’s a very labor-intensive craft,” he said. “There is no getting around that.”

Library director Elizabeth Pohl said the windows were so dirty and in such poor condition it was hard to discern their true colors. She said she’s impressed with the windows completed so far at the Stained Glass Express studio.

“They’re beautiful, like jewels,” she said. “They’re going to be such a lovely feature when they go back in and people can enjoy them.”