Southern California Rocks Please Identify For New Collector

No.s 1, 2, and 5 look a lot like granite

No.s 3 and 4 look volcanic, that is, derived from lava

Doubtless we will hear from others better at this sort of thing than I

farmerman is a geologist, I believe and he should have more insight...

still, its hard to pick out specimens from pebbles. There are a few examples of Porphyry in there ,as well as "varnish rock"

Much of the stuff is a combination of quartzites, mudstone and shale, igneous (granite, diorite, Alk porphyry, tonalite and some others that we need to look at closely.\\

3 and 4 are pumices or else "clinkers" from a furnace 5 and 7 are the pprphyries nd 8 and 6 are conglomerates with interesting chunks of earlier rock (we call these clasts) Its be neat to make a slab of this to see what youve got

If youre a collector, you need to get a book on mineralogy for

collectors and another on PETROLOGY, (so you can tell the rocks from the mins)


PS, I had a series of kitchen cab tops made from slab rock I came across in the field. I like the so much better than the same old same old "granite tops" they sell in the market. You can find a cabinet top "slabber" in Craigs list or even an old phone book

do some testing.
See which ones are harder than the others and get a copy of theHARDNESS SCALE for minerals.
Get some strong vinegar of weak hydrochloric acid (watch you dont burn yourself) . Dribble it on a couple that look plain greyish and see if they fizz. If they fizz, they are carbonates, like limestone, dolomite or siderite.

Doubtless, Jane

Thanks to all of you.

As an erstwhile rockhound, Saay3, you're entirely welcome

I say "erstwhile" because it sounds so much more impressive than "former"

Hi
I just started collecting rocks and I am reading a lot about them. Its only been two weeks so I don't know much....however willing to learn. You mentioned a slab ? I will look it up and see what that means but would like to know from you of what it means that it is clear to me.

a slab is a way of cutting a large rock . It forms what looks like a table top (a slab saw is a tools used to cut the rock)

People who make stone counter tops will have different sized slab saws.

Alright I got it and thank you for explaining.

That slab rock counter sounds interesting.