Inside the Conservation Lab: Dyeing silk for reproduction lampshades

When a historic object is beyond repair, a museum may make a reproduction to take its place on display. To recreate a pair of deteriorated silk lampshades from the Chapel Chamber at Beauport, the Sleeper-McCann House, in Gloucester, Massachusetts, Historic New England conservators started by dyeing a piece of silk to match the color of the original shades.

The original shades for these brass lamps no longer exist, but based on historic photos, conservators determined that they looked similar in shape and size to those pictured above. They were likely a brilliant green selected by Beauport’s owner Henry Davis Sleeper, an interior designer known for his bold use of color. A hint at the shades’ original vibrancy can be seen in a painting by William Ranken, which is on display in Artful Stories: Paintings from Historic New England, exhibition at the Eustis Estate in Milton, Massachusetts.

Dyeing silk to match a historic object is a multi-day process of careful measurement and notation. To start, conservators dyed a series of fabric swatches with differing ratios of yellow, blue, and black to create a variety of green hues and shades from which to choose. Pictured below are the white silk samples in their heated miniature dye baths—a mixture of water, dye, and additives to adjust pH and absorption quality of the fabric. Conservators then carefully raised and lowered the bath temperature over a period of time to ensure a lightfast, evenly dyed piece of fabric. After the samples finally dried, the fourth color from the left was the closest match to the original lampshade fabric.

With their color selected, conservators next needed to dye a large piece of silk to use in the actual reproduction. To ensure the color of the large silk piece was an exact match to the sample, conservators carefully measured and recorded the quantities in the dye bath, then multiplied them to match the increased size. Timing was also an important part of the process—pictured below, the dye and additives wait their turn in the continuously monitored and stirred bath. Luckily, the careful planning and math paid off, resulting in an evenly dyed piece of beautiful green silk. A specialty lampshade maker will now pleat and trim the fabric using the same methods from a century ago.

See if you can spot the lamps on your next trip to Beauport, opening for tours this summer.

Karen Bishop is the Mellon Conservation Fellow at Historic New England.