Stone-of-the-Day #13 is a small polished quartz-type stone from Riverton (Southland). It contains lots of small quartz crystal pieces, the biggest being in the centre of one side.
On Day 12 of Lockdown, 29 August, another polished Gemstone Beach stone has been chosen. This one is a thin flat red stone, probably jasper, with a couple of very fine veins.
Like many jaspers, it comes out of tumble polishing with an almost matte finish, not a high polish. Depending how it is held in relation to the light, its surface can appear matte or shiny.
This Gemstone Beach polished stone is likely to be the fourth last of the current stay-at-home Stones of the Day – there are strong indications that my part of the country will move to Level 3 restrictions on Wednesday.
Gemstone Beach is located on Te Waewae Bay on Foveaux Strait, in the far south of the South Island. It has a wide variety of stones, most of them already well-tumbled by the sea.
Stone of the Day #12 is here.
Today’s Stone of the Day is a small polished white stone, about the size of a one-dollar coin, a hydrogrossular garnet from Gemstone Beach near Orepuki (Southland). It is probably the most sought-after type of stone at Gemstone Beach, coming in a variety of hues including white, cream, green, brown and gray. It is especially shiny, standing out on the beach more than any other type of stone, and has a waxy feel to it.
Some people call these grossular garnets, others refer to them as hydrogrossular, so there is some confusion over their precise identification. Jocelyn Thornton, in her excellent booklet “Gemstones” calls the Orepuki stones “grossular” (see photo below left). As the “Encyclopedia of New Zealand” states: “Calcium-rich garnet is called grossular… A variety, containing some water, is called hydrogrossular and was first identified at the Roding River near Nelson. It is also found on the beach near Orepuki in Southland” https://teara.govt.nz/en/gemstones/page-3. The entry on “Rodingite” in “A Photographic Guide to Rocks & Minerals of NZ” (see photo below right) says: “The main minerals in rodingite are calcium-bearing hydrogrossular garnet, plagioclase and actinolite. Rodingites are recrystallised gabbro, basalt, sandstone or mudstone that has been saturated with hot fluids that deposit calcium… Rodingites formed from igneous rocks can be seen near Mossburn, Southland and as pebbles on the beach at Orepuki, also in Southland.”
Today, 70 new cases of Covid-19 were recorded in New Zealand, all in Auckland, bringing the total number of cases in the community outbreak to 347. Nineteen people are in hospital due to Covid-19, with one person in Intensive Care. It has been decided that, from the end of Tuesday 31 August, that part of the country south of Auckland will move to Level 3, a slight easing of restrictions, with indications that Auckland and Northland will remain in Lockdown for maybe a further two weeks.
Stone of the Day #11 is here.
Stone Nine is a small light-coloured stone from Riverton/Aparima (Southland), with interesting veins.
As of today, Thursday 26 August, daily Covid-19 cases are still increasing in New Zealand, with 68 new cases today and a total of 277 in the community from this outbreak of the delta variant. Only two cities are affected still, with most cases in Auckland and 14 in Wellington. An announcement will be made tomorrow about extensions of or modifications to the National Lockdown.
Stone of the Day #10 is here.
To start Week Two of our National Lockdown #2 in New Zealand, on Wednesday 25 August, this is a polished Gemstone Beach stone. It is probably made up mainly of quartz with iron staining giving it colour.
When I first starting collected stones for tumble-polishing, I would ignore these ones because I didn’t really like their rusty colour. However, after a closer look at their complex structure and the patterns that can be seen in them , I decided they were worthy of attention. They often have small holes in them that can be difficult to remove, and some of the iron-stained areas can be crumbly, as seen in this specimen. Not all such stones polish well but enough of them do so that I am always on the look out for them.
Stone of the Day #9 is here.
I have been posting the Stones of the Day on Facebook as well as on this Blog. Yesterday, my small personal Facebook community voted on a Stone of the Week for Week One. The outcome was that the rhyolite from Slope Point (Stone #3) was elected the first Stone of the Week.
Second place was Stone #4, the small multi-coloured stone from Kakanui.
Stone #8, the first of Week Two’s stones, can be found here.
Stone Seven is a small tumble-polished dendritic stone found on Birdlings Flat, just south of Banks Peninsula in Canterbury, sometime over the past couple of years. I was initially attracted to its cream colour with the additional black and brown lines and patches. It was only when working with the close-up images for this Post that I noticed the tiny fine dendrites in the stone.
The word “dendrite” is from the Greek word for “tree”, referring to the branching character of dendrites. In geology, dendrites are thin, branching crystals, often of some variety of manganese oxide (or iron), that grow over a surface in a rock or mineral. They are found in cracks or along bedding planes. Dendrites often look like fossil plant leaves but are, in fact, mineral crystals that form along a weakness in the rock as moisture moves through it. The brown dendrites in this stone, that have formed along fine black-coloured cracks, are not as sharp and clear as they often are in a stone, here appearing more fuzzy and diffuse.
On the seventh day of National Lockdown in New Zealand, daily cases of the delta Covid-19 variant were 41, having been 35 yesterday. That means there are currently 148 total cases in this outbreak. Daily cases should peak within the next three or four days, if the national strategy works. At present, the signs are good, with cases occurring in only two cities, 137 in Auckland and 11 in Wellington, although close contacts of cases are spread across the country. Eight people are in hospital with Covid-19, none in Intensive Care. Lots of testing is going on, contact tracing is proceeding, and the vaccination programme has sped up. Yesterday, the decision was made to extend the National Lockdown – Auckland will remain in Lockdown until at least the end of Tuesday 31 August (two weeks after the first case was identified) while the rest of the country will be in Lockdown until at least the end of Friday 27 August, with reviews to be undertaken just prior to these dates in the light of what happens in the outbreak.
Stone of the Day #8 is here.
Stone of the Week, Week One, is here.
Stone Six is a quartzite stone from Kakanui, North Otago. The most common colour for this kind of quartzite in this area is yellow, though some have red in them and others, like this one, are mainly a more neutral gray.
As the University of Auckland geology website states: “Quartzite is a metamorphic rock formed when quartz-rich sandstone or chert has been exposed to high temperatures and pressures. Such conditions fuse the quartz grains together forming a dense, hard, equi-granular rock.” What I find fascinating with these quartzites is how small clear quartz crystals become apparent in the close-up photos.
Stone of the Day #7 is here.
This trace fossil stone from Gemstone Beach (Southland) marks Day Five of New Zealand’s second National Lockdown. Daily Covid-19 case numbers are still climbing, but the positive effects of the Lockdown won’t be felt for at least a couple of days yet. Stone 5 is argillite, a hardened, slightly recrystalised, mudstone formed at the bottom of the sea millions of years ago (probably more than 250 million years for this stone).
Within the stone are captured the movements of small burrowing animals, with maybe a lighter coloured silt filling the burrow as the animal moves on. Or maybe the animal ingests the mud as it goes, excreting it behind itself in a pulsing movement, leaving the shape of an extended worm cast. Sometimes, eddies in the water can cause small ripples on the surface of the mud, and silt can gather in these ripples – and these can also be captured in a stone.
Stone of the Day 6 is here.