Unverifiable: we could not locate a live, official page for this product during research. It may be discontinued, renamed, or the brand may not maintain a findable page for it. This entry is preserved for transparency rather than removed.
Research notes
Not found on the official Marukyu Koyamaen English online shop. Checked the full 'Matcha' catalog (all 6 subcategories, 50 total product listings) and used the shop's own keyword search for 'Tsuki no Shiro', which returned 'No Products found.' Third-party retailers (e.g. narateacompany.com, sazentea.com) sell a Marukyu Koyamaen 'Tsuki no Shiro' ('White of the Moon') described as a Sohenryu-school ceremonial matcha favored by Master Shihosai, but this is reseller-sourced information, not from the brand's own site, so it is not included as confirmed/disclosed data here.