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1797 Discovery of Celestine near Bristol

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I very much enjoy connecting J.C. Sowerby's early mineral illustrations and descriptions to actual specimens.

In Sowerby (1804), he illustrates a distinctive specimen of celestine, shown below, from Aust in Gloucestershire, near Bristol.

He reports that a Mr. Clayfield had discovered "Sulphate of Strontian" here in 1797. "He observes that he discovered detached veins in different parts of the cliff. The strata in which the veins are found are nearly horizontal, consisting of Limestone of different hardnesses, and argillaceous Sandstone intermixed with Clay and Gypsum, and some of the fissures were filled up with Sulphate of Strontian from 3 to 12 inches in thickness."






I have an old specimen (shown in the three photographs below) which shows the same crystal form and orange staining. The specimen is 9 cm long and displays crystals to 3 cm. The label states an origin from the nearby Yates mine, but the crystals do not seem to be typical of specimens from there. …

Amazing Pittas of Kuala Lumpur

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Pittas are small short-tailed, multi-coloured ground-dwelling birds and a visual treat to encounter. General information on the pittas can be found here.

In this region, Alfred Russell Wallace (1869) used the distribution of pittas in nearby Sumatra to discuss problems in palaeobiogeography, noting the discovery on the small rocky island of Banca of "two new ground thrushes of the genus Pitta, closely allied to, but quite distinct from, two other species inhabiting both Sumatra and Borneo, and which did not perceptibly differ in these large and widely separated islands. This is just as if the Isle of Man possessed a peculiar species of thrush and blackbird, distinct from the birds which are common to England and Ireland." The Malay Archipelago, Chapter 9.

In and around Kuala Lumpur there are three species of pitta to be found; the mangrove pitta, blue-winged pitta and the hooded pitta.

I had met the mangrove pitta (Pitta megarhyncha) this June on Pulau Indah, near the port …

An Ancient Cornish Specimen of "Cubical Copper Pyrites" from Dolcoath

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Old mineral specimens can acquire fascinating veneers of history in addition to their scientific and aesthetic interest.

Shown here is one such example; not beautiful on the face of it, but full of interest, nonetheless.



An ancient mineral specimen from the Dalcoath Mine, Cornwall, about 7 cm across. Large chalcopyrite crystals, to 35 mm across, grow on a bed of quartz crystals, each to 3 cm long. Two generations of the iron carbonate siderite later partially encrusted both quartz and chalcopyrite, the last generation being a "dusting" of microcrystals.


On the evidence of its oldest attached label, the specimen was probably mined around two centuries ago. How can we tell? The oldest of several labels describes the specimen as follows:


"Black Oxide of Copper 
coating Cubical Copper Pyrites and 
Carbte of Iron on Quartz
Dalcoath Mine
Cornwall"

The old handwritten label accompanying the specimen illustrated above.

"Black oxide of copper" is a synonym for tenorit…

Svend Estridsen and the Vinland Colony

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I recently received an attractive coin of Svend Estridsen, which I like for the link with the North American expeditions of around a thousand years ago.

Svend Estridsen (Sveinn Ástríðarson in Old Norse) was born in England (ca. 1019), son of Ulf Jarl and Estrid Svendsdatter. Estrid was the daughter of King Sweyn (Svend) Forkbeard (son of Harald Bluetooth) and was sister to King Cnut the Great.

Adam of Bremen, the medieval chronicler, visited Svend's court and recorded accounts of Vinland he heard there in his "Descriptio Insularum Aquilonis."

"Moreover he[Svend Estridsen]spoke of an island in that ocean discovered by many, which is called Vinland, for the reason that vines grow wild there, which yield the best of wine. Moreover that grain unsown grows there abundantly, is not a fabulous fancy, but from the accounts of the Danes, we know to be a fact. Beyond this island, it is said, that there is no habitable land in that ocean, but all those regions which are beyond…

The Quokkas of Rottnest and early European encounters with marsupials

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18 km offshore from Perth, SWA, lies an island called Rottnest. It has rocky coasts with beautiful sandy bays. It also famously has quokkas and, as I am just starting to get to know this part of the world, I was keen to see some of these local marsupials. I spent a lazy day wandering around the island on Saturday 2nd September 2017.



Rottnest, just offshore Perth. Notice the spectacular submarine canyon further offshore.

The sandy beaches and rocky coastline of Rottnest.

Disembarking from the ferry, I went for a walk in a nearby forest to look for quokkas. It didn't take long before I encountered the far-from-active specimen shown below.


My first encounter with a quokka, a sleepy individual in a small forest


A sweet and docile couple

A friendly face


The first Europeans known to have landed on the Rottnest were 13 Dutch sailors from the Waeckende Boey who touched ground near Bathurst Point on 19 March 1658 while their ship was careened nearby. The ship had sailed from Batavia (later…

Primate Paradise of Gunung Leuser, Sumatra

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Gunung Leuser National Park is not very far from Kuala Lumpur as the crow flies. A hop over the Makasar Strait and a journey of around 120 km from the metropolis of Medan up to the forested hills.

In practice, the journey takes much of a day, including an hour in the air and four to five hours to cover the ground betwen Medan and Bukit Lawang. We made the journey last weekend for a couple of days of trekking and wildlife watching.

A short hike from the friendly village of Bukit Lawang, over one of the bridges suspended across the river, past rubber trees in a small plantation, takes you to the entrance of the Gunung Leuser National Park.

A short while later we met the first of three new (to me) primate species, the North Sumatra leaf monkey (Presbytis thomasi), charming with their crests and impish faces.










Alfred Russel visited Sumatra from November 1861 to January 1862, but further south, where he also encountered Presbytis monkeys (presumably the mitred leaf monkey).

"In Sumatr…

The Spectacular Great Argus

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In "Into the Heart of Borneo," Redmond O'Hanlon describes hearing a loud call in the Borneo rainforest and being convinced that it was made by gibbons. I too have heard this call, in the forests of Batang Ai, Sarawak, and it sounds like this.

Last weekend, hiking through the forest of Gunung Leuser National Park in Sumatra we heard the call several times again, our guide saying that it was coming from a couple of kilometres away.

After a long hike involving some very steep descents and ascents we heard the call again, but closer. Then, walking on, a large elongate form in a dense thicket became visible. As I walked around, I found a small gap in the leaves and took the following photograph of the brilliant blue head of the originator of the call, a male Great Argus pheasant.





We watched for a while and then backed off as he moved out into a more open area where we could appreciate the spectacular form and design of the bird - and it's astonishing size.





Argusianus argu…