Pieces of silicified limestone (tripoli) from conglomerate and limestone unit

These fragments of tripoli chert from the conglomerate have unusual
markings. In addition to the complex distribution of cream, peach, and
maroon coloration, the rock is laced by thin white veinlets that super-
ficially resemble the strands of a spider web. Their slightly curved
shapes suggest they represent fillings of subconchoidal fractures that
formed within the tripoli bodies; veinlets in the sample on the right are
curved to the same degree as bounding fracture surfaces, and are
parallel to some of them. The regions of peach coloration seem to
represent transitions between the original color of the tripoli and more
strongly stained portions, but close examination reveals a complex
pattern of color distribution that defies a simple explanation. Note
especially the intricate "medallion" marking in the lower portion of the
left sample between the 6 and 7 cm positions.

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