Americans call them Yooperlites

I will try and add a Youtube vid on what the title calls Yooperlites. Two days before this video appeared I picked up a stone almost identical to the stone at 19 seconds, stop the vid and see.
In daylight the stone is mottled / speckled grey, whites and blacks. So I got into the hall closet with the stone and a UV torch and there it is, the same identity as the one in the video.
Clearly, I reside in Australia and here were these stones, on our beach. I suspect that they are a porphyritic andesite / volcanic breccia, but investigation reveals:

Andesite Porphyry:
Occasionally, andesites contain large, visible grains of plagioclase, amphibole, or pyroxene. These large crystals are known as "phenocrysts." They begin forming when a magma, which is cooling at depth, approaches the crystallization temperature of some of its minerals. These high-crystallization-temperature minerals begin forming below the surface and grow to visible sizes before the magma erupts.

When the magma erupts onto the Earth's surface, the rest of the melt crystallizes quickly. This produces a rock with two different crystal sizes: large crystals that formed slowly at depth (known as "phenocrysts"), and small crystals that formed quickly at the surface (known as "groundmass" . "Andesite porphyry" is the name used for these rocks with two crystal sizes.

This beach also has specimens of lace agate and a very suspicious stone that has a lot of nephrite qualities about it, which I will suss out further with a density test, etc, as soon as I get a round tuit.

Watch: https://youtu.be/-rb6AbcCfU0

or: http://youtu.be/-rb6AbcCfU0

Here you are.No excuse now Pat

Here is the video that Pat linked (twice) above:

[video=480,360]https://youtu.be/-rb6AbcCfU0[/video]

Where is the photo of what you found yourself. The "Yooperlites" (what will the Americans think up next) is actually a sodalite-bearing rock, which is the mineral that fluoresces in them.

https://www.bing.com/images/search?...te&form=IGRE&first=1&scenario=ImageBasicHover

Sodalite is not terribly common in Australia - we get it in half a dozen places, usually in sodium-rich syenites and similar rocks. e.g. with the relatively uncommon mineral leucitite (e.g. Olary, Mt Dromedary, Cygnet SW of Hobart, Jingera, the Warrumbungles, and Tomahawk River and Boat Harbour in northern Tasmania). So I wonder if you have a new locality, or if it is a different mineral that fluoresces in your samples?

Sodalite does not only occur in sodium-rich igneous rocks as in Australia, but in metamorphosed salt deposits i.e. the sodium in this case coming from sodium chloride salt), where it is associated with the gem lapis lazuli (the mineral lazurite, not to be confused with a different blue phosphate mineral called lazulite). Lazurite is chemically similar to sodalite. Theoretically it might occur with metamorphosed salt in places like Cloncurry and Olary. I don't know of any gem quality lapis lazuli in Australia.

Nephrite is just as rare in Australia, and is mined at Cowell in South Australia - it is the greenstone that maori's make various things out of (often called "jade"
although it is not the valuable jade mineral, which is jadeite). We get minor occurrences in other places like Tamworth, Ogunbil, Spring Creek, Mulla Creek and Nundle in New South Wales, with very mnor occurrences near Inverell, Port Macquarie, Mount Lawson and Orange in New South Wales. We have no jadeite at all, it only forms at very high pressure at great depths (e.g. 50 km), but at depths where it is cooler than normal (unisual at great depths), so is only brought up from below at a few localities around the world.

So keep it up!