title: Radiocarbon dating of biogenetic opal.
abstract: Approximately 75 grams of biogenetic opal were isolated from 45 kilograms of soil by employing gross particle-size and sink-float specific gravity fractionation procedures. After pretreatment of the sample to remove extraneous organic and inorganic carbon contaminants, the carbon occluded within opal phytoliths was dated at 13,300 +/- 450 years before the present. Therefore, biogenetic opal is stable for relatively long periods.
authors.forename: L P
authors.initials: LP
authors.lastname: Wilding