John S. Dickey, Jr., 1972. "A Primary Peridotite Magma-Revisited: Olivine Quench Crystals in a Peridotite Lava", Studies in Earth and Space Sciences, R. Shagam, R. B. Hargraves, W. J. Morgan, F. B. Van Houten, C. A. Burk, H. D. Holland, L. C. Hollister
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Serpentinized peridotite layers in the Early Precambrian (3.4 b.y.) Onverwacht Group of the Swaziland Sequence, South Africa, appear to have been lava flows. These flows, which are interlayered with metamorphosed pillow basalts, display pillow structures and chilled, ultramafic margins. A specimen of the chilled peridotite has a quench texture consisting of serpentine pseudomorphs of bladed olivine crystals with interstitial plumose tremolite, probably pseudomorphous after dendritic clinopyroxene. Analyses of relict olivine (Fo88) in the chilled and normal peridotites show unusually high Ca content (0.2 to 0.3 wt percent CaO).