Subsurface Laboratory Methods 147 



Mottled: Residue fragments with two or more colors or different material 

 interspersed and irregularly shaped with the boundaries between either sharp 

 or gradational; often appears flocculated; grades into speckled residue. 

 Oolite: Composed of an aggregation of ooliths. 



Oolith: Spheroidal bodies with nucleus or central mass enclosed by one 

 or more surrounding layers of the same or different material; may be any color 

 and of many kinds of material, generally less than 1.0 mm. in diameter. Those 

 over 2.0 mm. are pisoliths. 



Concentric: Peripheral layers around a small, undetermined 

 nucleus. 



Clustered: Attached ooliths without solid matrix. 

 Drusy: Oolith covered with subhedral quartz; may be free 

 or clustered. 



Free: Unattached oolith. 



Massive : Interior of granular, smooth, or chalk-textured mate- 

 rial comprising nearly the entire mass of the spheroid. 



Radiate: Fibers radiating from small or large nucleus; may 

 have several peripheral layers. 



Sand-centered: Nucleus, a quartz sand grain. 

 Oomold: Spheroidal opening representing the former pres- 

 ence of ooliths. 

 Oomoldic: Containing oomolds. 



Skeletal with oomolds: Same definition as for "dolomoldic." 

 Abundant oomolds: Same definition as for "dolomoldic." 

 Scattered oomolds: Same definition as for "dolomoldic." 

 Ordinary: smooth chert with even fracture surface; all colors, chiefly 

 white, gray, or brown; may be mottled; approaches opaque; generally homo- 

 geneous, but may have slight evidence of granularity or crystallinity ; grades 

 into chalcedonic or granular chert. 



Porcelaneous: Chert with smooth fracture surface; hard; opaque to sub- 

 translucent; typically china-white resembling chinaware or glazed porcelain; 

 grades to chalky. 



Pseudoolithic: Rounded pellets with no peripheral layers or sharp dis- 

 tinction between pellets and matrix. 



Quartz: Clear, colorless quartz; not detrital. 

 Radiate: See oolith." 



Regenerated: Used in reference to quartz sand grains with secondary re- 

 growth of crystal faces oriented with the original axis of the grain. 



Rounded: Spheroidal or ellipsoidal sand grains, coarse to fine, may be 

 polished, frosted, or etched. 



Sand: Grains of sand size, chiefly quartz, but may be composed entirely or 

 partly of other minerals. 



Sand-centered: See "oolith." 

 Scattered: See "dolomoldic" and "oomoldic." 



Silt: Grains of silt size, chiefly quartz, but may be composed entirely or 

 partly of other minerals. 



Skeletal: See "dolomoldic" and "oomoldic." 



Smooth: Major type of chert with conchoidal to even fracture; surface 

 devoid of roughness; may be botryoidal; homogeneous; no distinctive struc- 

 ture, crystallinity, or granularity. 



Spicular: Containing inclusions of sponge spicules. Free spicules have 

 been noted. 



Speckled : Disseminated fine spots of color or material different from that of 

 the matrix and having relatively sharp boundaries. 



