Japanese Wood-fired Shigaraki Natural-Ash-Glazed Kōgō/Incense Case, Gingko Leaf Motif
A small Shigaraki incense case (kōgō) by ceramic artist Kiyoko Kohyama, shaped in the form of a ginkgo leaf. Compact and sculptural, the piece follows the distinctive fan-like silhouette of the leaf, with gently incised veins radiating across the lid and softly irregular edges that preserve the character of the maker’s hand.
The case is composed of two fitted sections, with the ginkgo leaf-shaped lid resting over a slightly lighter-toned base. Its warm reddish-brown surface is punctuated by pale mineral specks characteristic of Shigaraki clay, while subtle variations in color and texture reflect the effects of wood-kiln firing.
The piece is finished with shizen-yū, or natural ash glaze, created as wood ash settles onto the clay during firing and melts at high temperature. Rather than forming a uniform surface, the ash produces understated areas of sheen and tonal variation, allowing the natural texture of the clay and traces of the firing process to remain visible.
When closed, the kōgō reads as a small sculptural ginkgo leaf. The incised veins, gently curved edges, and fan-shaped form give the piece a quiet sense of movement, while the fitted construction reveals its function as a small container for incense.
Through the combination of Shigaraki clay, natural ash glazing, and wood firing, Kohyama allows material, fire, and natural form to become the primary decoration. The result is a tactile, understated object that balances function with the organic beauty of the ginkgo leaf.
Dimensions: W 2.3" x L 3" x 1.5 H "
About Kiyoko Kohyama: Kiyoko Kohyama, also romanized as Kiyoko Koyama, was an important Japanese ceramic artist associated with Shigaraki, one of Japan’s historic pottery centers. Born in Nagasaki Prefecture, she moved with her family to Shigaraki during the wartime period and became deeply interested in the area’s ancient kiln sites and archaeological ceramic fragments. Those discoveries helped shape her lifelong interest in reviving the natural surfaces and firing methods of early Shigaraki ware.
Kohyama became particularly known for working with anagama, traditional wood-fired tunnel kilns in which prolonged firing allows wood ash and flame to interact directly with the clay. Rather than relying primarily on applied glaze, she pursued surfaces created through the firing itself—earthy color, ash deposits, flashing and irregular textures produced by clay, heat and fire. She established her own kiln and became one of the notable women working in a field that, especially at the time, was heavily male-dominated.
Her importance also extends beyond her own ceramics. Kohyama trained younger potters—ceramist Kazue Tsukuda, for example, apprenticed with her for two years—and became part of a generation of Japanese women who expanded the possibilities for women working independently with demanding wood-firing traditions.
Her life later became widely known through her advocacy for bone-marrow donation after her son developed leukemia. Her story inspired the Japanese feature film Hi-bi: Days of Fire, released in 2005, in which actress Yuko Tanaka portrayed Kohyama.
In relation to the small flower-shaped piece you photographed, it is useful to see it within this larger practice: even at an intimate scale, the emphasis on tactile clay, irregular handmade form, earthy coloration and the physical character of the material connects naturally with Kohyama’s broader commitment to pottery grounded in Shigaraki clay, fire and direct contact with the hand.
