According to the decisions of the Congregation of Rites chasubles must not be of linen, cotton or woollen stuffs, but of silk; though a mixture of wool (or linen and cotton) and silk is allowed if the silk completely cover the other material on the outer side; spun glass thread, as a substitute for gold or silver thread, is also forbidden, owing to the possible danger to the priest's health through broken fragments falling into the chalice.
And poised on its top most bough, a crystal crescent moon glistened like spun glass.
While it is easy to install because it is in roll form, gloves and a mask over the nose must be worn to prevent breathing in the small spun glass fibers or getting them embedded in the skin.