Visitors to the Straus Center for Conservation and Technical Studies can witness conservators at work as well as view 2,500 pigment samples placed in tincture bottles and housed behind tall glass cabinets. These "medicines" are used to doctor faded artworks.
The Forbes pigment collection at Harvard Art Museums was started by Edward Forbes at the turn of the 20th century. He collected samples from his travels all over the world, bringing back pigments from excavated sites at Pompeii to rare lapis lazuli found in Afghanistan.
You can see an electronic directory of these materials through the Museum of Fine Arts, Boston’s Conservation & Art Materials Encyclopedia Online (CAMEO) database here.