This popped up on my feed. I'm a 'yank (duh...) Your Gabbro looks like our Granite; specifically the living granite that's pristine, unmolested, and preserved underground. *(But as in a "boulder" state, regardless of mass and density/size. Not a "lift" or extended mass) Hardness out of this world. Basalt? Everywhere up here 'mate, every gazillionth of a degree as hard as granite...Absolutely as hard as living granite, but basalt can be exposed at the surface & STILL be a hard. Crazy stupid hard. I've operated the "hammers" that pulverize these top tier minerals (since '79) and there's NO substantial difference in my work attack to render either into any type of sizeable quantity. So I'm subscribing now to rewire my brain! Or what's left of it lol. Cheers! ---------------- PS Wait 'til you hear about the red caliche. RED. CALICHE. Camelback Mountain. Arizona USA. Again well over 8 mohs. +++ Fairytale stuff. HARD This caliche defies crushing work. Nothing but salts/powders when attacked with 2,000'+ hammers. And the space is too precious to over excavate, so the landowners capitulate to above ground engineering experiments to satisfy formally available underground systems. It's a living 'guv! WINK!
That is fantastic. The specimens I have come from the University of New England, plus I collect other specimens based on geological maps. I have no doubt you can look at a rock and see how it will affect your work, that experience is valuable. Caliche is called calcrete in Australia, and it occurs in the basalt where I live, though it is sold and can be broken with the hand, so is recent. Your caliche sounds old.
Gabbro is one of my favorite igneous rock types. I'm lucky to live near gabbro outcrops and collect some decent specimens. I've got some larger specimens of metagabbro which are pretty cool looking. My last video uploaded may actually be a piece of metagabbro, though I'm not changing the description from "green basalt" as I haven't positively identified the exact composition yet and the metamorphic alteration makes identifying minerals more difficult. There are visible zones of serpentinite, with some minor calcite and massive magnesite veins. The magnesite is silicified, so figuring out the Moh's hardness is about impossible. Half of the rock looks like a green granite gneiss. It's very rich in olivine, epidote, diopside, chromite and feldspar, so I'm really trying to grasp the order of mineral formation of this material. Two things I know for sure are it's dark green and very heavy. :) I'm gathering a bunch of specimen material to send off to be examined by someone with much more expertise than me, so I'll hopefully find out in the near future how successful or incorrect I was in identifying these minerals.
Sounds interesting. I also have trouble identifying minerals in rocks. But the Geo maps of Victoria are pretty extensive, so it helps alot. We do not have any gneiss in vic, so you are lucky, and meta gneiss, more lucky. Thanks mate. Will check out your video.
Thanks for the great video. By the way, is that a dog hair on the vasicular basalt at 3:31? My dogs "guard hairs" seem to make their way onto everything!
That would be more complicated than chemistry. You would have the latitude which bring moisture and temperature, as well as biological aspect. As Gabbro have a larger grain size it should affect the short term outcome. Basalt derived clay is horrible and only useful for grazing, and my home is cracking because of the shrink swell properties.
