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Thursday, 19 October 2017

THE INVERELL METALLOGENIC MAP AND MINE DATA SHEETS


LIST OF ALL BLOGS AND RELEVANT YOU TUBE VIDEOS

Before reading this blog, it would be best to read the similar blog about the Grafton-Maclean map. This may be found here. The relevant reference number for the map and mine data sheets in DIGS is R00056102.


The Inverell package may be found by opening DIGS here. The reference number is R00050906 (which includes the map). The reference number for the map alone is R00027907.


The Inverell map seems to be a poorer copy than the Grafton-Maclean one, making an enlargement harder to read.

You will soon appreciate what a large number of mineral deposits there are in the area, including at The Gulf (north west of Emmaville), Tingha and the Copeton diamond fields.

Here is an extract from the map. 
 To illustrate the information to be found in the Mine Data Sheets, I’ve chosen the deposit number 585. The location is south of Inverell, east of Copeton Dam. Fortunately for us, the data sheets are in a single volume, not dismembered like the Grafton sheets are. Upon opening the data sheets you will find quite a lot of valuable information on the geology of the region and the nature and formation of the many mineral deposits.
The data sheets commence on page 104. Deposit 585 will be found on page 377. Here is the information.
 This is a typical set of information, in this case for Fox’s Garnet Lode. I must admit I can’t locate it on the map – it’s quite a congested area – but the information is all there for you to use. Mindat (here) provides additional information when the deposit name is put in the search box. Here is what I discovered. 


By following the map Mindat provides (and choosing the satellite image) you will discover that the Lode is just north of the Howell Road, which leads to the old town site of Howell and the Conrad group of mines.

Slide show to accompany this blog: here

Wednesday, 11 October 2017

THE GRAFTON-MACLEAN METALLOGENIC MAP

The NSW Geological Survey has compiled an extensive series of reports which can be used to assist in the search for new mineral deposits or simply to locate existing ones. The Grafton-Maclean Metallogenic Map group of documents may be downloaded from DIGS (here) using this reference number: R00056102. The files take up about 65 MB and consist of many related documents apart from the map itself. These represent the original report broken up into sections.
The map includes the Torrington and Emmaville districts and extends southwards to Glencoe. The western edge of the sheet joins the Inverell map, and it extends to the coast in the east. The Inverell map will be the subject of a later blog.
The map provides a vast amount of information – geology, structure and mineral deposits as well as the underlying topography, roads, watercourses etc. This can make locating something quite difficult and frustrating, so it’s important to become familiar with the meaning of the colours and symbols provided around the margins of the map. Here is an example of what the map contains:

The rest of the documents in the downloaded folder provide information on the background geology and the individual mineral deposits. Take, for example the deposit number 1837, roughly in the centre of the extract. The table of mineral deposits (left of map) describes this as “Back Plain Creek sapphire (Zr)”.
You will find the deposit listed in the file titled “Text_4.3MB_zip_of_4_deposit;_pdf” (the first of four of these). When the file is open, scan through until you come to “GR 1837”, which is the extract below.
More information can be found by looking up the Mineral Occurrence List in the second part of the above file, using the same deposit number (1837).
 You could expand your knowledge of the area by searching other deposit numbers nearby, whether you can find them on the map or not.
Another possibilty is to search the Mindat data base (here) using the mine name. This is what you will find for Back Plain Creek:
Located approximately 15kms NNW of Glen Innes.
Operated as a small open cut and shallow pits 1971 to 1990s.

Mineral List



2 entries listed. 1 valid mineral.

The above list contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.

References

Metallogenic Study and Mineral Deposit Data Sheets: Grafton-Maclean Metallogenic Map (SH/56-6, SH/56-7), Geological Survey of New South Wales, 2001: HF Henley, RE Brown, JW Brownlow, RG Barnes and WJ Stroud. Published by the Geological Survey of New South Wales.

Finally, you might like to check out my blog on the Back Plain Creek area here.
Here is a link to a slide show of pictures from the data package: here.

Sunday, 5 February 2017

STAGGY CREEK GEM FOSSICKING AREA NEAR INVERELL NSW AUSTRALIA


Extract from "Diamonds in NSW"
Staggy Creek reserve is one of the few places in NSW where fossickers can go and have at least some chance of finding an alluvial diamond. It’s part of an extensive deep lead lying beneath the basalt, south of Inverell. Tin (cassiterite) was the main mineral being sought by miners in this area in the nineteenth century and diamonds were discovered during the search. This created a lot of interest at the time – and still does, judging by the amount of prospecting that has been going on during the last twenty years. Search DIGS (here) using “Staggy Creek” as the locality and you will be surprised.
There’s a lot of good background information in my Blog “Alluvial Diamond Mining in the New England Region of NSW Australia” (here) and especially in the NSW Geological Survey publication “Diamonds in New South Wales”. You can download a copy from DIGS; the reference number is R00047949.
I’ve been there just once, at least 25 years ago. All I can remember finding is pieces of black tourmaline, which are everywhere.
Here’s what the Inverell Tourism website (here) has to say about Staggy Creek:
Copeton diamonds - Australian Museum
The district’s rich volcanic soils can offer other gems and minerals. One such gem, is the amazing Diamond found near Copeton Dam; the Staggy Creek Fossicking Area provides a site where you can look for the Diamonds together with Black Tourmaline and Quartz. This is a rough dry area 28km from Inverell, you can take your water or dry sieve.
Contact Details: Copeton Dam Road (24km from the turn off Copeton Dam from Inverell)”      
This is what “Diamonds in NSW” has to say about the place.
Photo courtesy of Jewellery Pirate
The Staggy Creek deposit is an isolated area of diamond-bearing Tertiary gravels exposed at the surface. There is no basalt overlying the deposit and granite bedrock surrounds the Tertiary gravels. The granite is remarkable in that it contains a number of potholes of circular shape and its surface appears to be the surface on which the Tertiary sediments were deposited.
The deposit consists of quartz pebbles, cobbles and boulders ranging from 5mm to 0.2m in diameter, jasper, a relatively large amount of tourmaline (much of which is unabraded), topaz and garnet (which is invariably present in the diamond bearing gravels). Many of the quartz boulders contains pencil tourmaline. An ironstone band similar to those at Kirk’s Hill and the Banca is present.” Read page 52 of the report for a fuller description.
Mindat (here) includes a reference to Staggy Creek.
Photo courtesy of Jewellery Pirate
Staggy Creek lead, Copeton DamHardinge Co.New South WalesAustralia
Latitude & Longitude (WGS84):
29° 50' 5'' South , 150° 53' 5'' East
Latitude & Longitude (decimal):
Map sheets: SH 56-5, 9038-II-N. Coordinates: 295600mE, 6697500mN.
Placer deposit.
Rather strangely, the Mindat list doesn’t include ‘tourmaline’, the most obvious mineral at Staggy Creek.
Here is a list of other resources you will find interesting.
Photo courtesy of Jewellery Pirate
Jewellery Pirate’s Blog (here). Thank you, JP, for the photographs of Staggy Creek.
An account of a visit by the Campelltown Lapidary Club (here).
Paul Clacher’s visit (here).
All Travels website (here).
World of Shiny Stuff website (here).

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 re-sieving 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