New orby Rio Grande Jasper

I wanted to mention Mel. Sabre52
I went to the Rio upstream from Brewster County, down stream along Big Bend, a spot upstream from Laredo, and then down at Lake Falcon/Zapata(Uvalde size)..
What I noticed is the rocks/cobbles got smaller the further down stream travelled.
North of Brewster County boulder size cobbles were everywhere.
Zero boulder sized cobbles around Zapata.

I am guessing you are collecting these Rios upstream from Laredo ?
Or Eagle Pass territory. Never could find an access around Eagle Pass due to private ranches. Tried.

I also wanted to visit CJ Young ranch on Brazos. Famous for colorful well silicified conglomerates.
Location mentioned in Gem Trails. Probably closed now. I found fine conglomerates in Zapata.
Perhaps washed down from Brazos.

James, The most common size from the ranch these come from is about four inches. Largest Clayton has brought in from there is about 15 pounds but the large ones tend to be golden moss and often sugary in texture. Largest high quality agate I've ever found in the Eagle Pass gravel at my buddy's rock yard was about ten pounds. Gotta figure nodular agates are usually just not that huge, even when you see them in situ. I have seen hundred pounders years ago at Woodward, moss not plume, but those were rare. I know Stillwell has some huge boulders there though. The ranch these come from is in Carrizo Springs SE of Eagle Pass and is unhunted as it used to be a military base. I suspect there are large ones there and more palm too but it does take a trained eye to find unwashed specimens unless wet. That dang caliche tends to make all the boulders look alike.

In the Eagle Pass gravel I often hunt there are spectacular agatized breccia examples and some quite large too. Most tend to be larger than the agates. Got one in the pile I want to try and cut that came from Carrizo Springs too but I don't know if I can get the darn thing in my little saw vice.....Mel

Bob, the ranch is huge ( these are really "rich" oil men I guess, if they can buy a whole military base) and runs right to the river bank. Occasionally, Clayton will bring by an agate that is all river washed and clean of caliche because it's fresh off the river bank. But yes, the actual name for the Rio grande gravel is the Uvalde Gravel because that's where they were first surveyed, and Uvalde is a long ways from the modern day Rio Grande. Many deposits, as a matter of fact, some of the best, are high on the slopes way above the current river level. The Rio was gigantic back in the Pluvial periods, as were the Frio and the other south Texas streams....Mel