Southern African Lapidary Stones to watch out for

September 25, 2018

Verdite

Verdite is a fairly soft South African stone found in the Barberton area. It is often seen in African curio shops carved into animals. Its golden flecks distinguish it from buddstone which is a much harder metamorphosed chert. Even more distinctive is the “leopard rock” which is spotted serpentinite, also from that area. JW

 

Buddstone



Leopard rock

 

 

FaceTips for September

August 24, 2018

By Duncan Miller

Here is a quick and easy oval with a standard 1:1.30 proportion. It has a fully conical pavilion, so you can spin a conical preform, stopping just short of producing a point. This means you don’t have to change angles and mast height when cutting the sixteen pavilion facets, which saves time and avoids mistakes. This is a fully meet-point design that doesn’t require a preform, so it would be good for a beginner’s first oval. It doesn’t work well in quartz or beryl, s...


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STAVOREN MICROMOUNT OUTING

August 24, 2018

Jako Schonken

I arrived at OR Tambo airport on a cold winter’s Thursday morning, hoping it wouldn’t rain. I hired a car and started driving in a northerly direction, following my GPS to Marble Hall - a place I have only heard about in the South African Micromount Society’s newsletters. I have been a member of the South African Micromount Society (SAMS) for more than three years, but have never been to their meetings or outings since they are based in Gauteng. Nor have I ever met any of...


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FaceTips for August

July 25, 2018

By Duncan Miller

Jewellers sometimes ask for the impossible, and it’s a challenge to try and oblige. This design was developed to cut the citrine for a dome-shaped ring. It had to be a ‘classical’ mixed cut with curved girdle lines to match the curve of the top of the ring. This design requires a preform to get the girdle facets the right size. The relative depth of the pavilion tiers affects the angles of the triangular corner facets, but these can b...


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Southern African Lapidary Stones to watch out for:

July 25, 2018


SODALITE – this is generally sourced from Swartbooisdrif, near the Kunene River in north-west Namibia. It has a Mohs hardness of between 5,5–6, is generally fine grained, and works very well.

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Encouraging the Curiosity of the Next Generation

July 25, 2018

Matt Lurie (5 years old), who lives in Johannesburg, was curious as to the make-up of an (amethyst) Spirit quartz crystal so he bought one for R10 in Johannesburg and de-jacketed/exfoliated/peeled it, to satisfy his curiosity! The images below were taken by his dad (Robert’s son) Dan Lurie.

   


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Zeitz Museum of Contemporary African Art

May 24, 2018
Once the grain silos of Cape Town Harbour

Built in 1923 the old silos in Cape Town Harbour were used for storing grain awaiting export, and were in operation until 1995. Today they house a modern art gallery. Thanks to the generous sponsorship of Jochen Zeitz, (former CEO of Puma) and the incredible architectural imagination of the Heatherwick Design Studio, the building is now a magnificent place to visit. The old round tubes of silo have been cut away in specific places to open up a central ...


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Faceting

May 7, 2018

Here are two stones that Duncan Miller cut recently from rough he bought two months ago at Open Day. The yellow citrine (from Johann de Jongh) has only 58 facets, is 22 mm wide and weighs 37 ct. The design is ‘Xephyr’ by Arya Akhavan (yes, with an ‘X’). The light green fluorite (rough from Rob Smith), is the first one he has ever cut. It has even fewer facets, only 36, is 15,5 mm wide and weighs 16,2 ct. The design is slightly modified from ‘Six Shooter’ by the late Jeff Graham.  ...


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Visit to Mineral Services and the Exhibition “Messengers From The Mantle”

March 29, 2018


By kind invitation of Professor John Gurney, 25 club members visited Mineral Services on 24th February to see his exceptional exhibition “Messengers from the Mantle”. This irreplaceable collection of kimberlites was initially created for the 35th International Geological Congress at the Cape Town International Convention Centre in September 2016, and was displayed again at the 11th International Kimberlite Conference in Gaborone, Botswana in Septembe...


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Field Trip to Yzerfontein

March 29, 2018
Sunday, 18th March

Pictures speak louder than words.


Brunsvigias alongside the West Coast road


24 members learning about an example of gabbro


Coastal erosion from the winter storms of 2017


An igneous breccia dyke


A 70,000 year old archaeological midden


Inspecting rocks on Schaapen Eiland


Iron pyrites


Inclusions of gabbro in the breccia dyke


Inclusions of chilled wall rock in the monzonite

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