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Japanese Natural Stone (JNATS) Strata Information


Ai ishi naori (合石成り):
honshiro, nakashiro, tenjou tomae, naka tomae, shiki tomae.
Stones from this strata tend to be coarser & softer than those from Hon kuchi
or Chu ishi naori. Hideriyama stones are from this strata.

Hon kuchi naori – 本口成り「ほんくちなおり

Shallowest Strata -> Deepest Strata

  • Aka pin「赤ピン」
  • Tenjou/Tenjō suita 「天上巣板」(てんじょうすいた)
    (4 layers/strata: uchigumori, nagagumori, sotogumori, shiro)
  • Hachimai 「八枚」 (8 layers)
  • Senmai 「千枚」 (2 layers)
  • Tomae 「戸前」(とまえ) (48 layers)
  • Aisa / Ai – sa「合さ」(あいさ)
    (4 layers; Karasu is sometimes found in this strata)
  • Namito / Nami to「並砥」(なみと) ~ Daijyo / daiji yo
    「大上」 (だいじょう) (8 layers)
  • Hon suita「本巣板」(ほんすいた) (6 layers)
  • Shiro/shiki suita「白巣板 / 敷巣板」(2 layers)

The last 2 layers are also described slightly different:

  • Hon suita「本巣板」(ほんすいた) / Shiki suita 「敷巣板」(しきすいた)
  • Shiki shiro「敷白」 (しきしろ)

On “Maryuoyama (Mt. Maruo)” the 7th layer from the top,
“Namito / Nami to「並砥」 ~ Daijyo / daiji yo「大上」”,
is called “Daijyo / daiji yo「大上」”

(the mines around Mt. Atago, west (nishi mono) and east
(higashi mono), are of the Hon kuchi naori type, the quarry
of Atago itself is of the Chu ishi naori type)

Chu ishi naori (中石 成り): has no distinct difference
within the Naori, meaning there are no distinct layers,
Atago for example is a Chu ishi naori type

Example of different “strata” in a “Hon kuchi naori”:

The mountain Maruoyama (丸尾山, Western from Atagoyama),
Kyoto is of the “Hon kuchi naori” type of geology.
Following are different layers (strata), together with the type of extracted
stones within each layer, (from shallowest to deepest) (1):

  • Tenjō suita (天上巣板) →  Uchigumori (内曇)
  • Tomae (戸前) → Tomae (戸前), Tenjō Tomae (天上戸前),
    Hon Tomae (本戸前), Shiki Tomae (敷戸前)
  • ai (or aisa, 合さ) → Aisa (合さ), Karasu (“crow”, カラス)
  • Namito (並砥) or Daijyo / daiji ~you (大上  「だいじょう」)
    → Oujou (?, 大上), Suita-Giwa-Daijyo (巣板ぎわ大上)
  • Shiki suita (敷巣板) → Shiro suita (白巣板 = “white Suita”), Tamagoiro Suita
    (卵色 = “yellowish coloured Suita”), Kiiro Suita (黄色 = “Yellow/Amber Suita”), Kurorenge (黒蓮華 = “Black Renge”), Shiki utigumori/Shiki uchigumori
    (敷内曇 = “Clouds on the floor – deep Uchigumori layer”)