show me your conglomerates and breccia

[snowmom]

I have been busily collecting conglomerates, tillites, brecchia and the like. I have one small piece in black matrix that somebody tumbled and gave to me as a gift. It looks like stained glass. I'd love to see photos and hear discussion of tumbling these things. I realize the parts are the sum of the whole and the softest rock in the bunch will determine the course I take in tumbling them. Discussion desired... teach me what I need to know? thanks! : )

[jamesp]

It's hard to know till you tumble them. many are glued together well w/silicas. They should tumble well if healed together w/silicate.
Looking at the surface of the one on the left it looks like it has worn equally; that's a good thing. the one on the right looks like it has undercut.
this one is spastic from Zapata Texas

[Sabre52]

Lots of varieties of these from the Eagle Pass gravel beds. I usually just put them in the garden because they can be real saw stoppers to cut and most are huge, way too big for my ten inch saw. Got this one slab off before it stopped the saw....Mel



And of course Stone Canyon Breccia:



Hornitos Breccia:



Boar Canyon Breccia:



Creston Jasper breccia:



Big Sandy Creek brecciated Jasper:



Stephanite ( sometime Stephoinite) breccia:



Lavic brecciated jasper:



Bodie Jasper a conglomerated out of Oklahoma:

[washingtonrocks]

Here's something a little bit different. Not the prettiest stuff in the world. lol. But fairly unusual. It has a uniform hardness so no tumbling problems or undercutting. Sort of has that stained glass effect you're talking about.

Chert Breccia





Here's a cab I made. Same type of rock, different specimen.

[quartz]

We pick up some material on the Oregon coast that looks very similar to what you show, granted very distant origin, and it looks good and polishes up really nice. Hope yours does well. The odd part is that people step right over it, likely thinking it's no good.

[bhiatt]

dino conglom with fortification


and the proof that it is bone

[bhiatt]

nother dino conglom

[snowmom]

those are all great!So many colors and varieties! I really think I like these things more than anything else I have seen so far. It adds a whole 'nother dimension to rock. bhiatt I had no idea dino could do that, though I can't think of a reason why it shouldn't once it is rock like all the others... amazing! I am glad to see others find these interesting too, they are very common here and there is much variety in both stone and matrix. I am anxious I could ruin one when it comes time for the tumbling and the polishing... would hate to lose one of my favorites while trying to make it shine!
So should I treat it like quartz or granite with lots of smalls to reduce motion and improve chances of fewer chips and dings? I would be using mostly a vibe for these, rather than actually tumbling... good idea?
has anybody got examples of pudding stone ? I find many bits of that and it seems quite stable for the most part, so again, treat like quartz? thanks for all the pictures, I could look at a thousand more. Any comments on problems or solutions you ran into while processing these is good, too!

[iant]

It can be hit or miss tumbling, with the harder rock taking on a high shine and the softer rock remaining matt. Makes for a really interesting piece. Better in the flesh,  hard to appreciate on the screen. 

[Drummond Island Rocks]

The Michigan variety of pudding stone can vary quite a bit. The stuff with a real white matrix seems to be the worst for tumbling but some like these do better. I have had pudding stone iin just about every batch for the last three years so lots of experience with that particular stone. I will tell you that it cabs much better then it tumbles and what I tumble is usually my cabbing scraps or pieces not big enough to slab and cab.

I consider these to be about as good as I get tuumbling this stuff


And here was what the average stuff comes out like. You can really see the undercutting in the white matrix here.


Chuck

[luvtogrow]

Llagas creek

[luvtogrow]

Llagas creek

[snowmom]

helpful info, wondrous photos...thanks to all (more welcome, please!)

[Deleted]

here is a green/purple conglomerate gifted to me by @azrockgeek. Perhaps he'll illuminate us on what it is. My feeble brain remembers "kjefiuhuh mine down near Tucson..."

shown wet, no polish





cr@ppy images, sorry. It's really nice.

[snowmom]

ooh, I see lots of cool pastels... love pink and green together....

[Fossilman]

I just cut this one the other day...Found it on the river....

[garock]

Great Photos ! So many different types of conglomerates !

[jamesp]

Jun 22, 2014 8:36:14 GMT -5 Fossilman said:

I just cut this one the other day...Found it on the river....

nice one Fossilman. Like the pork colors. Hard sandwich meat.

[Fossilman]

Jun 22, 2014 11:55:31 GMT -5 jamesp said:

Jun 22, 2014 8:36:14 GMT -5 Fossilman said:

I just cut this one the other day...Found it on the river....

nice one Fossilman. Like the pork colors. Hard sandwich meat.

Head cheese! LOL

[washingtonrocks]

Here's some Porphyritic Andesite that fits nicely into the conglomerate category. This stuff's volcanic in origin and is pretty easy to find close to home. It generally consists of Plagioclase crystals in a Pyroxene or Hornblende matrix. I've never tried tumbling these for some reason, but I do have plenty of rough cut up and ready to go when my tumblers are finally freed up.