ニュージーランド，オケテのベイサナイトおよびそのかんらん岩捕獲岩とメルトの反応物中のかんらん石，スピネルを記載した。かんらん石斑晶は二種類に大別できる。斑晶 (I) (コアでFo₈₅-Fo₇₆, リムでFo₇₆) は小型で自形性が高く，非変形で，細粒スピネルを包有する。斑晶 (II) (コアはFo₉₀ 以下で均質，リムはFo₈₅-Fo₇₆ の正累帯) は大型で，自形∼他形である。コアは変形組織を有し，リムのみスピネルを包有する。斑晶 (I) のうち，低Fe³⁺ グループのスピネル (高Cr#) を包有するものは，かんらん岩中の斜方輝石とメルトの反応物起源，高Fe³⁺ グループのスピネル (低Cr#) を有するものは，メルトから結晶化したものであろう。斑晶 (II) は外来結晶 (かんらん岩起源) 起源で，化学的，形態的に様々な改変を受けている。ピクライト玄武岩やアルカリかんらん石玄武岩のような，かんらん石斑晶に富む火山岩中のかんらん石斑晶は，メルトとかんらん岩との反応により，多起源性たり得る。

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The mode of occurrences of gageite from manganese ore deposits in outer zone of the Southwest Japan were investigated. Twenty six occurrences of gageite, beside locations reported by Fukuoka and Hirowatari (1988) and Matsubara and Kato (1979), were newly found from high P/T type (pumpellyite-actinolite facies to zeolites facies) manganese ore deposits distributed in the southern and northern zone of Chichibu belt in the Kii Peninsular, Shikoku and Kyusyu district. Gageite occurs as a principal constituent mineral of altered braunite designated as chocolate ore, which is chocolate-colored massive ore composed of various minerals with high Mn content, locally as veinlets, and form tabular and fibrous crystals of 2-3 mm order in length. Two occurrences of gageite are distinguished. Gageite is commonly accompanied by rhodo-chrosite, alleghanyite and hausmannite with minor ribbeite, pyrochroite, kellyite, barite, cymrite, and sussexite. Gageite, also, occurs rarely as thin laminated layers with caryopilite in the banded rhodochrosite ore. EPMA analyses indicated that gageite is chemically characterized by low Mg content, however their Mg contents are generally larger than those in closely coexisting alleghanyite. The occurrence of gageite suggests that gageite in chocolate ore have been formed later than alleghanyite as an alteration products from braunite ore under the high f  H₂O condition. On the other hand, it is assumed that laminated gageite in rhodochrosite ore is primary mineral formed under the low grade regional metamorphism.

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