Search This Blog

Sunday, 1 January 2017

BLATHERARM CREEK TORRINGTON TOPAZ FOSSICKING




Blatherarm Creek (Blather Arm Creek, Blather Creek) is one of the most popular fossicking areas in the Torrington (NSW) district. This is partly due to the provision of a camping area there, but mainly because of the many topaz cutters which the creek gravel produces.

The map has been extracted from a publication of the NSW Geological Survey called “Rocks, Minerals and Landforms of the Mole Tableland which appeared in 2014. The DIGS reference number is R00059626. DIGS is a site from which a vast number of useful references can be downloaded. (here) I haven’t visited Blatherarm for more than 20 years so I have made use of some photographs from the Australian Lapidary Forum site (ALF here).  Thank you to those who contributed these to ALF.

The earliest reference to topaz at Blatherarm that I have found is in TWE David’s monograph on the
Vegetable Creek Tin-Mining Field (DIGS reference R00031676) page 70, where he writes “The sand and clay in these alluvial workings, in portion 42, parish of Bates, county of Clive, are from 10 to 15 feet deep, and consist of subangular granite sand, with subangular and rounded quartz pebbles up to 6 inches in diameter and rest on a bottom of granite. White topaz and sapphires are very abundant.”


Other Geological Survey references dealing with the area have this to say. “The Mole Granite area is also well known for topaz crystals ranging in colour from clear to straw yellow to blue and up to several centimetres in size. Topaz crystals or fragments can be found in all creeks draining the central Torrington pendant. The topaz originates from numerous silexite or quartztopaz bodies that mainly occur within the Torrington pendant or from the numerous narrow silexite dykes within the Mole Granite. Blather Arm Creek is particularly well known for its clear and blue topaz crystals and a significant amount of topaz has been found in Scrubby Gully and Highland Home Creeks.”


It was later found that the presence of rare corundum in local creeks was commonly known by local miners and fossickers. Other known localities are Blatherarm, Cattarrh, Bald Rock and Slow Gully Creeks. The source of the corundum is unknown but may be derived from the remnants of high level Tertiary gravels.”

I’ve mislaid my source for these quotes, but they are probably from Industry 18: Mineral Industry NSW - 1980 - Gemstones (2nd Edition) (DIGS reference R00050830), Exploration Data package Clive 1:100 000 sheet (DIGS reference R00031737).

Other documents you could consult include these:

Jewellery Pirate’s blog (here), a Mindat article (here) and the Minerama book (Topaz 1995) (here).

Beryl also turns up in the Blatherarm gravel. It is the typical pale green colour of Torrington beryl and is usually opaque. You cannot concentrate beryl in the sieve centre the way you can topaz because its specific gravity is nearly the same as that of quartz. You will need to look through the stones in the sieve to find any.

The source of the beryl is probably Bollinger’s Lode, which outcrops on private land upstream of the
Conservation Area boundary. Resist the temptation to trespass on this or other adjacent land. The best topaz fossicking is in the permitted area anyhow. Most of the land upstream appears to be swampy. When I was last there, I found most of my topaz by dry sieving old dumps away from the creek (top sieve only), collecting the sieve contents in a bucket and then resieving this material in the creek.
It is worth noting that radioactive minerals have been discovered at Bollinger’s and nearby locations. Torbernite is the most abundant of these. See Bollinger's Prospect, Torrington (DIGS reference R00039360)

Sunday, 4 December 2016

TOURMALINE IN QUARTZ LOCALITY WALLANGRA NSW



Photo by Wwoofa via the Australian Lapidary Forum
This is a well-known mineral collecting locality in northern NSW, on the western edge of what is commonly called the New England region. Unfortunately it is a place I’ve never visited so I am depending on the descriptions of others.

The Inverell Tourism website has this to say: “Wallangra Fossicking Area. Wallangra located north of Inverell has an area near the hall where you can hunt for Black Tourmaline in Quartz, once again this is a dry fossicking area. Contact Details: Wallangra Hall, Wallangra (65km north of Inverell) Ph: (02) 6728 8161.”

You may not find that particularly helpful. Knowing that the spot is near the Hall is good, but you also need to know that this is on the left hand side of the Yetman road. I’m sure you will find the place OK without ringing Wallangra. 
The spot is open freely to fossickers. Please do the right thing and leave your mechanical diggers at home. As well as your specimens, take home all your rubbish and other people’s as well if you come across any.

There is a stack of information available on the Australian Lapidary Forum. I suggest you become a forum member so you can access it. Here. You can then contribute to the Forum by telling members about your visit to Wallangra.

There are a number of websites describing visits to Wallangra. “Frosty’s Aussie Adventures” (here) should answer most of your questions. Thank you Wayne for showing us what should be available from the Inverell Tourism website.

I will point out at this stage that Wallangra and Wallangarra are quite different places. The latter is just across the NSW border into Queensland on the New England Highway.
This is an extract from the Inverell 1:250000 geological map. It shows that Wallangra is situated in an area marked Pg (Permian Granite, actually part of the Bundarra Suite).
The Australian Stratigraphic Units Database contains this definition of the “granites” of the Bundarra Suite:
Coarse- to very coarse-grained, porphyritic and equigranular (biotite)-(muscovite)-(garnet)-(cordierite) granite and leucogranite; K-feldspar megacrysts abundant in places.” This is the host rock in which the Wallangra tourmaline in quartz bodies are found.

I have been unable to find any account of the detailed geology of the occurrence.
Mindat (here), however, regards the site as significant. Here is what a search on the location produces:
“Latitude & Longitude (WGS84):
29° 13' 54'' South , 150° 53' 4'' East
Latitude & Longitude (decimal):
Located south of Texas, Qld.
Wallangra (in Northern New South Wales) was the site of a quarry, the area is now a designated Fossicking area. There is a quartz outcrop which contains tourmaline.

You will notice that the word ‘tourmaline’ is in quotes. This is because tourmaline is the name of a mineral family, rather than an individual mineral. In this case, the mineral is schorl – commonly called black tourmaline. If you want to read more about the tourmaline group, check this Mindat reference here.
Photo by Wwoofa via the Australian Lapidary Forum
Photo by earthound via the Australian Lapidary Forum

Wednesday, 3 August 2016

THE TIN-MINING INDUSTRY IN NSW BY JE CARNE (1911)



The complete title of this book is “The Tin-Mining Industry and the Distribution of Tin Ores in New South Wales”. It is No. 14 in the Mineral Resources series, produced by the Geological Survey Branch of the NSW Department of Mines.
You can download a copy from DIGS (here). DIGS is an on-line collection of publications made available by the NSW Department of Industry (Resources and Energy). The reference number is R00050677. This book is an important resource for anyone interested in mining history and especially those wanting to locate and identify old mines and mineral deposits.
I have prepared a slide show using the numerous plates from this book (viewable on my YouTube site here).
I wish to acknowledge the source of these photographs now and thank the
Geological Survey of NSW for making this resource available.
You will soon see if you look through the DIGS listings that there is a huge volume of literature on the subject of tin mining in NSW. Much was written before 1911 and a great deal more since. The New England region was at the heart of the industry. Locations such as Emmaville, Torrington, Tingha and Wilson’s Downfall stand out. Today, however, little mining is going on and it will take a substantial increase in the price of tin to get things moving again. The emphasis then will be on large scale mining and it looks as if the day of the solitary miner or small syndicate is over.

Here are the reference numbers for some other important documents relevant to the subject of tin mining.
The Mineral Resources of NSW (1901) by EF Pittman. DIGS reference number R00051137
The Mineral Industry of NSW by EC Andrews et al 1928. R00050818
Tin (Bulletin No 1) by EJ Kenny 1922. R00050981
Minerama book 1994 Cassiterite downloadable here.