Found this material in close proximity to the material we just posted about last week. Maybe a half mile further South of the mountain, Jocotenango, near Antigua, Guatemala. Old volcanic area. Not sure how old. According to the internet the area has been erupting for millions of years. I am assuming that all of the mountains are mostly volcanic ash, pyroclastic flow, etc.
This material appears to be Pumice (or Volcanic Tuff, actually) with a brecciated Jasper (or something similar) in the matrix. I have never heard of that so am asking for opinions.
The red material in question is very hard, at least a 7 on the Mohs. Steel knife / scissors / chisel doesn't touch it. Also appears to be small crystals throughout, assuming Amphibole and Biotite pieces.
The third image shown shows what appears to be the hard red "jasper" material before it silicified enough to become harder.
Would you consider this Silicified Tuff? Or Brecciated Jasper in Tuff? Or does it not really matter? :)