雲母引・具引

In addition to gold and silver leaf, which were extremely popular, mica (called unmo or kira in Japanese) was used to add sparkle to the paper. For example, this is a fragment of a waka poetry collection written in the 11th century; it is just a tiny portion of a larger scroll and it may be a little hard to see, but here and there there are small shiny dots. The effect was obtained by sprinkling powdered mica on the paper, a technique known as kirachirashi (“mica sprinkling”). In kirachirashi , the paper sparkles only in some places, whereas in this example here the powdered mica was mixed with nikawa glue and then applied to the entire sheet.

It is similar to parts of this example, but with this type of decoration, called kirabiki or “mica coating” the entire page has a glossy finish. Another technique that contains the word biki in the name is the gubiki or “shell white coating”. Instead of mica, the white powder is made from seashells, which is known in Japanese as gofun (shell white). When gofun is mixed with nikawa glue, it produces a white paint-like substance that can be applied to the paper; this process is known as gubiki. Colors can be added to the white powder to produce thick color paper. This one here is an example of a book that has been decorated in different colors using the gubiki technique.

Thus, mica powder and shell white were commonly used to embellish and add color to the paper.