Category: New Zealand

Birdlings Flat I: What the Books say

Birdlings Flat is a beach about an hour’s drive from Christchurch in the South Island of New Zealand.

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Display in Birdlings Flat Gemstone and Fossil Museum

Lyn and Ray Cooper (1966), New Zealand Gemstones, Chapter 2 “Where to Find the Stones”: Birdlings Flat in Canterbury was, at one time, an excellent source for agates, but supplies are now much harder to find there, mainly because of the area’s close proximity to a large city and the swarms of collectors who have combed it over the past year or so. Good agates can still be found there, but the best time is immediately after a storm, when the sea has turned the surface stones over. (page 28) 

Mrs A. Niethe, “Gemstone Localities: New Zealand” in Bill Myatt (ed.) (1972), Australian and New Zealand Gemstones: How and Where to Find Them: Birdling’s Flat (it is named after the late Mr Birdling, who had a farm there) is part of the shingle spit, some 15 miles long, enclosing Lake Ellesmere. Half-a-dozen rivers along the coast to the west carry these gemstones from the hills inland to the sea. For millions of years the set of the current has swept the gravels north to pile against the basalt cliffs of the Banks Peninsula…  This is the Mecca of New Zealand’s rockhounds, famed for a variety of gemstones that reads like a geological dictionary. Coloured quartz of many types is the most common – jasper; chalcedony, mostly clear or grey or white, sard, sardonyx. petrified wood of various colours – a lot are fractured, after a while you only keep the perfect ones… Stones reached this beach from many parts of the South Island, presumably through glacial action in the ice ages. Rhodonite has been found here, quartzite, jasper from the Livingstone Mountains to the south-west; prase and plasma from the Hinds River, 60 miles away to the west, and true jade as Maori artefacts. Beware, this beach is extremely dangerous. Turning one’s back on the sea to pick over the rising bank of pebbles is almost involuntary, but it is very risky at Birdling’s Flat where the big waves knock you off your feet. (page 436)

Natalie Fernandez (1981), The New Zealand Rockhound, Chapter 5 “Locations”: Hundreds of rockhounds have cut their teeth on Birdlings Beach – just a short run from Christchurch. Here great rollers break on the stony shore throwing forward stones with a roar as the waves thunder up the steeply shelving beach and sucking them back with a clatter as the waves recede. You can look for your agates and jaspers well back from the water-line but they do not show up clearly unless you dig down, for only the surface layer is dry. More exciting is to hunt along the water’s edge. As a wave slides back an agate is spotted. You leap for it but miss as the next wave roars in, driving you back. You never see that agate again. The beach is steep and the undertow strong. The breakers are especially powerful in a southerly and on the in-coming tide. Few can play this game and keep dry. (page 14)    

Fernandez Birdlings Flat
“Birdlings Beach” following page 16, Fernandez, The New Zealand Rockhound

Natalie Fernandez (1981), The New Zealand Rockhound, Chapter 5 “Locations”: Birdlings Flat is 26 miles from Christchurch on the Akaroa Road. Shingle beach for 15 miles. There are still some pickings especially with a N.W. wind and an incoming tide. During a Southerly with rough seas the stones are sucked away again. A slight easterly with calm weather builds up the beach again. There is a strong under-current. The great rivers flowing into the Canterbury Bight bring material from inland to the sea. The current brings them north to be deposited where Banks Peninsula forms a barrier. Petrified wood, jasper, grey clear chalcedony, sardonyx, agate. In 1965 the beach was gazetted as a reserve. It is dangerous. (page 114)

Other TumbleStone Posts on Birdlings Flat:

Birdlings Flat II: Location Map and Satellite View (May 2016)
Birdlings Flat III: Selection of Online Sources (May 2016; up-dated 2019)
My Visit to Birdlings Flat, Day 1 of 2 (May 2016)
My Visit to Birdlings Flat, Day 2: Gemstone and Fossil Museum (May 2016)
My Visit to Birdlings Flat, Day 2: Stone Collecting (May 2016)
Birdlings Flat Stones After First Stage of Polishing (May 2016)
Polishing Agates from Birdlings Flat: Stage One (May 2016)
Another Visit to Birdlings Flat, Late June 2016 – Part One: Taumutu
Another Visit to Birdlings Flat, Late June 2016 – Part Two: Birdlings Flat Gemstone Museum Again
Another Visit to Birdlings Flat, Late June 2016 – Part Three: Seven Types of Stones Collected
TumbleStone Calendar 2019 – February, March, April and May

Stones in the Process of Tumbling

These stones have undergone the first stage of tumbling with 100 grade silicon carbide grit. Most of them are from Riverton beaches, in Southland, but a couple are from the West Coast of the South Island (New Zealand). Some will need more tumbling in this coarse grit because they still have small pits or scratches not yet smoothed away.

Where Agates Can be Found in New Zealand

NOTE: 3 July 2019 – The mineralworld website referred below is no longer available currently on the internet. I have therefore included in square brackets below access to this material via the Internet Archive, as it existed in 2016-2017.

Mineralworld [see archive] is a website developed by Klaus Schäfer, [see archive], a German gemstone expert and jewellery-designer, who has done a lot of research and writing about gemstones, especially agates and jasper. He refers to his site as an “agate-almanac” – it is all about agates. An agate can be described technically as a translucent cryptocrystalline variety of quartz, a variegated chalcedony, characterised by colours in alternating stripes or bands, in irregular clouds, or in moss-like forms. Agates may have a wide variety of colour patterns and banding, with the many distinctive styles and patterns virtually making each agate unique. 

There are many pages on Klaus Schäfer’s website about agates worldwide, with a multitude of excellent and beautiful photos from a wide range of collections. Some of the information and articles are in German but there is much English material there as well.

Part of the website is called “Agates Worldwide” and has detailed descriptions of thousands of places where agates can be found. One page is the Index to the New Zealand material [see archive] where 28 locations are listed (such as Birdlings Flat, Hinds River, Nimmo’s Swamp, and Ward’s Beach). Click on a location and you are taken to a page with a description of the location and the agates that have been found there (usually written by NZ experts), illustrated with exquisite agate photos [NOTE: The Internet Archive very unfortunately did not archive these photos, but some agate photos can be found elsewhere on the archived site – click here for examples], four of which are below. The localities of origin of the agates in these photos are, from left to right: Nimmo’s Swamp, near Moeraki in Otago; Rangiatea Station near Mt Somers, Canterbury – this photo is by Malcolm Luxton who has recently published a book on “Agates of New Zealand” (see my comments on Luxton’s book in the section on Stone 11 in “Twelve Stones, Part Four“); Whitecliffs clay pit in Canterbury; and Gawler Downs Station near Mt Somers, Canterbury.

These agates were large enough to slice through so that their banding and internal patterns are shown to best effect. If agates are too small for this, they can be tumble polished like other small stones.

Regarding agates on TumbleStone, see also the following Posts: A) My Visit to Birdlings Flat, Day 2: Gemstone and Fossil Museum; B) Another Visit to Birdlings Flat, Late June 2016 – Part Three: Seven Types of Stones Collected; C) Polishing Agates from Birdlings Flat: Stage One; D) Stone #11 in Twelve Stones, Part Four; E) Milestone #6 in Nine Milestones at Journey’s End; F) The May page in TumbleStone Calendar 2019 – February, March, April and May; and G) Stay-at-Home Day Twenty-Six, Monday 20 April 2020: Stone Twenty-Six. 

“Australian and New Zealand Gemstones: How and Where to Find Them” edited by Bill Myatt (1972)

This large hardcover book was published in 1972 by Paul Hamlyn – it measures only 24cm by 19 cm but its 511 pages makes for a thickness of 5 cm. It had a nice sized font which makes easy reading, is well-illustrated and well-written, and is a mine of detailed information written for the interested layperson (only some of which is dated).

Aust NZ Gemstones cover

I obtained my second-hand copy, in excellent condition, from K-books in Scarborough, Ontario, Canada, through online retailer Abebooks, for just over NZ$50 (shipping included), with only 2 weeks between ordering and arrival.

The book is made up of four main sections: “General Information” pages 9-59, including fossicking methods, mining law and making jewelry (there is great advice on fossicking in the Australian outback, where safety considerations are significant); “Geology” pages 61-137 (with pages 123-130 being on New Zealand); “Gemstone Identification” pages 139-283 (very readable text on the major types, with only the rare black and white photo but with a 32 colour plate section showing many rock types in their natural form); “Gemstone Localities” pages 286-503 including 35 high quality colour map guides to main gem-bearing areas. New Zealand localities are discussed in pages 430-448 and 497-503, sections written by A. Niethe (“New Zealand Gemstones”), W.F. Heinz (“Gold”) and M. Jepsen (“Thermal Regions”). There are entries on the following areas: Coromandel Peninsula, East Coast, Northland, Canterbury, Dunedin, Greymouth, Invercargill, Nelson, and Oamaru. Detailed comments are made of where certain types of rocks have been found, as well as on very practical topics such as road conditions and accommodation in these areas. Of course, most of this information is now out-of-date, written over 40 years ago, but it provides great starting-points for the contemporary rockhound as well as much interesting historical material.

The publisher aimed to produce “a comprehensive book on Australian and New Zealand Gemstones, suitable for the ordinary reader”, with the Localities section presented as “the most detailed account ever attempted”. Lapidary, Gem and Mineral Clubs contributed significantly to the book, as did academic and technical experts on geology and minerals – the result was outstanding and much of its value has not been lost over the decades.      

Front of dustjacket and front foldover
Contents, first 2 sections
Contents, last 2 sections
Page 168 and part of page 169 – Beginning of entry on “Chalcedony” in “Gemstone Identification” section
Colour plate: “Spotted jasper found near Coober Pedy, South Australia; Inset: An old house on the Coober Pedy Opal Field”
Colour plate: “Agate Creek, Canterbury NZ; Insets: Polished Canterbury agates, and Canterbury agate seen in section”
Part of page 430 and page 431 – Start of New Zealand entry in “Gemstone Localities” section
Map showing main gem-bearing areas of the Coromandel Peninsula, NZ
Map showing main gem-bearing areas of Nelson, NZ

 

 

 

 

“Rock-collecting sites in New Zealand” – An Online Map

In Te Ara, the online New Zealand Encyclopedia, is a map of beaches in New Zealand where you can find agates and other interesting stones.  This is a very selective map and does not include, for example, Riverton at the bottom of the South Island, one of the best places for semi-precious stones. 

sites

“Gemstones” by Jocelyn Thornton (1985)

“Although New Zealand lacks the commonly accepted ‘precious gems’ (diamond, ruby, sapphire, emerald), many local stones deserve our recognition” (from the Introduction to “Gemstones”).

This booklet, originally published in 1985 in the Mobil New Zealand Nature Series, is long out-of-print but now available online as a pdf file. The pdf file is 36 pages long (each of its pages consist of two of the original booklet pages when its comes to numbering – the original booklet numbered each side of each sheet, making 74 pages). It is a great source of information on the range of precious and semi-precious gemstones to be found in New Zealand – from greenstone to agate to jasper to petrified wood, and many more. It contains some great photos of the many different types of stones, supplemented with notes on where these specimens have been found (see below for the entry on “Carnelian”). Reference is often made to places such as Birdlings Flat, Rangitata River,  Orepuki, Kakanui, Mt Somers, the Coromandel Peninsula, and Takaka.

Joyce Thornton also wrote the entry on “Gemstones” for Te Ara, the Online NZ Encyclopedia. This entry has some excellent photos of different types of stones, such as “Silicified Wood and Plant Material“. “Chert, Flint and Jasper“, and “Greywacke Pebbles with Quartz Veins“. In 2004, she received the NZ Order of Merit for services to Earth Sciences.

Source: https://teara.govt.nz/en/interactive/5124/silicified-wood-and-plant-material
Source: https://teara.govt.nz/en/interactive/5123/chert-flint-and-jasper
Source: https://teara.govt.nz/en/photograph/5121/greywacke-pebbles-with-quartz-veins

“The New Zealand Rockhound” by Natalie Fernandez (1981)

This is the second significant New Zealand book published on rock tumbling (after the Coopers’ book), though its scope is broader, “rockhounding” in New Zealand in general. I ordered this book through Amazon and they sourced it from Bookhaven, a second hand bookstore in Wellington.

fernandez cover13042016

“The New Zealand Rockhound” by Natalie Fernandez was published in 1981 by Boughtwood Printing and Publishing House, Auckland. The book measures 14 cm by 21.5 cm and has 191 pages. Beach stones, my prime interest, are only one form of rocks – they are very useful for stone polishers because they are already relatively smooth and rounded, already the subject of hundreds of years of “tumble polishing” in rivers and ocean. Rockhounds need to be able to identify rough and dirty rocks in the field – all I have to do is wet a beach stone and decide if I like the result.

fernandez contents13042016“The New Zealand Rockhound” covers rockhounding in New Zealand in general. Chapter Six, “The art of the lapidary”, starts off with five pages on rock tumbling before going on to discuss cutting and grinding and other means of working with rocks and stones.  Chapter Four on “Rocks and minerals” provides an introduction to the topic in the context of New Zealand’s geology, and Chapter Five, “Locations”,  provides an annotated list of NZ places to find interesting rocks.

Fernandez’s book also has a delightful frontispiece of stamps with rocks and fossils on them:

fernandez stamps13042016

 

 

 

“New Zealand Gemstones” by Lyn and Ray Cooper (1966)

On the way home from our South Island holiday, once the seed had been planted that we would start polishing stones, in Wellington I visited three second hand bookstores in search of books on rocks and rock tumbling. I found this book at that time, probably the first New Zealand book on rock tumbling.

CCF13042016

“New Zealand Gemstones” by Lyn and Ray Cooper was published in 1966 by A.H. and A.W. Reed, Wellington. It is a hardback book, 22 cms by 14 cms, 125 pages long and cost me $20 at ArtyBees secondhand bookstore.

The key chapter for me at this early stage was Chapter Three, “How to tumble-polish”. It is now a bit out-dated in parts, as new technology has since changed some aspects of rock tumbling, but it provided me with the basic ideas about what tumble polishing involves and what its key principles are. 

contents coopers13042016Chapter Two was the next most interesting, “Where to find the stones”, the location of interesting stones in New Zealand based on the authors’ own expeditions to different places. Again, some of this information is now out-dated and is at least partly constrained by the authors’ experiences (there are some parts of the country they have not been to), but provides an invaluable starting point. (Their comments led me to take a trip to the Coromandel Peninisula beaches not long afterwards.) Chapter Six, “What to do with stones”, was on a topic that I realised I would need to pay some attention to sooner or later.