A natsume (棗) or usuchaki (薄茶器) is one of the traditional containers for Matcha tea powder for usucha (薄茶), or thin tea in the Japanese tea ceremony. They come is several sizes, shapes, colors and compositions.
The one pictured here is a lacquer design called Akebono. This size natsume is a Chu, or middle size natsume. It can be made of layers of lacquer over a wooden form or lacquer over a plastic form. The one using the wooden form is more auspicious, but the one with the plastic form is usually less expensive and is good for practice.
This particular motif of black lacquer with a little bit of orange lacquer showing through comes from the early days of lacquerware where orange lacquer was rare. This design lets you use just a little bit of orange lacquer to the greatest effect.
The popularity of this design has also brought us the opposite design, which has a little bit of black showing through a mostly orange coat. This design is called Negoro. The names for Akebono and Negoro are often mixed up, because of the Western similarity of Negoro to the word black, but this is not the case. Here, Negoro is named after The Negoro-shū who were an order of warrior monks based in Negoro-ji temple, in Japan's Kii Province.