This extraordinary matcha chawan is an exclusive handcrafted nerage marbled clay work created by master potter Nagayama, representing an extremely intricate ancient ceramic marbling technique that yields utterly one-of-a-kind art pieces. The entire vessel’s body is formed by manually twisting and folding multiple tones of raw clay together before wheel-throwing. This labor-intensive nerage marbling process locks in organic, swirling brown and cream vein patterns that permeate both the bowl’s exterior walls and its inner cavity. No two marbled swirl layouts can ever be replicated, making this chawan a genuine singular art piece with an entirely unique natural stone-like texture. A thin transparent matte glaze overlays the marbled clay, preserving every delicate swirl detail while delivering a soft, warm tactile finish ideal for holding matcha tea. The base features a hand-trimmed unglazed foot ring, revealing the raw marbled clay cross-section and showcasing the potter’s authentic hand-finishing craft. This chawan arrives complete with its original hand-inscribed wooden tomobako presentation box. The box lid bears the master’s brush signature “Nagayama Zou (長山造)”, the work title “Matcha Chawan”, and a red artist seal, delivering full traceable provenance to confirm the piece’s authentic maker origin. The tea bowl is preserved in flawless near-mint unused condition, free of chips, cracks, glaze loss, stains or any signs of tea ceremony use. Handcrafted nerage marbled clay chawans with intact matching artist-signed tomobako boxes are vastly scarce on the global collector market. Marbled clay pottery demands far longer production hours than standard solid-clay tea wares, leading to limited yearly output from master artisans; most surviving nerage tea bowls have lost their original storage boxes over decades of collection. This piece functions perfectly as a premium daily-use matcha tea bowl for traditional Japanese tea ceremony practitioners, and also stands as a striking decorative display highlight for collections of rare hand-manipulated studio pottery and wabi-sabi East Asian ceramics. This is a rare acquisition chance for discerning collectors to own a fully documented, unused master marbled clay matcha chawan.