sponges?

[hndmarshall]

posted this a while back and was told it may not be a sponge but an odd cert well just found another...now not so sure...I am really leaning toward some sort of sponge again as the second is a little larger but the same cup shape with an attach area.

[JohnJ]

Some things to keep in mind about the gravels you are searching...most are cherts, jaspers, chalcedonys, quartzites, and other variations of those rocks.  They are sorted by size at the gravel dredging companies.  The ones in your area of Texas likely come from ancient gravel deposits in the upper terraces of rivers north and west of Houston.  The age of the quarry deposits are unrelated to the age of the gravels.  They have undergone thousands of years of erosive cycles.  Most softer type rocks don't make it into these deposits.

 

Chert comes in an incredible amount of colors and variations.  Many of the 'impurities' in banded or variegated chert are relatively soft.  These layers and enclosed pockets erode physically or chemically.  Their pitting and other unusual textures are often the result of this erosion.  So, even though fossils are found in Texas cherts, one must consider natural geologic occurrences as the most common origin.

[Bronzviking]

I agree with John, not sponges, just rocks. Rocks can be just as interesting though.

[hndmarshall]

ohwell will keep looking but hanging onto them in my foss-not box