Bill James (Australia) writes:
Wind, rain frost and chemical reaction with gases in the atmosphere, smash and decompose the hardest rocks. Running water is the world’s most energetic miner. It carries vast loads of material to sea with every rainfall. Rivers and streams carve away the faces of mountains, pounding rocks into pebbles and sand. Where the stream rushes swiftly, the bedrock is scoured; where it loiters, the gravels carried in the water are left in what are called alluvial deposits.
These deposits contain the heavy insoluble materials washed from the rocks, including gold and gemstones. Rain falling over a mountain range sweeps into the river systems of the area the debris of rocks already decomposed by exposure to air and the alternate effects of frost and sunshine. In this way rivers concentrate deposits of both gold and gems that are far richer than those contained in the original rocks.
But many things can happen to a river in a few thousand years. Most likely it will change its course several times, each time leaving gem gravels high and dry and creating fresh deposits in new places. Rivers have been gathering gold and gems from the rocks of Australia not for thousands of years but thousands of million of years. Time and again the landscape has changed. Where once a river flowed from east to west, it is diverted to flow from north to south. What was once a streambed becomes a mountain-top; sea invades the river valley, smashing the rocks with its waves. Or perhaps a huge glacier, most ruthless of nature’s jackhammers, grinds across the land, carving mountains to new shapes, leveling valleys, carting heaps of rock and gravel many miles to faraway places. Glaciers left their mark on Tasmania and New South Wales and scattered a thin trail of diamonds as they rasped across the highlands of north-eastern Victoria. In one place ice blocked the rivers; in another, fire. Lava from a volcano flowed over the diamond field of Copetown in New England some 40 million years ago burying a riverbed under up to 130 ft. of basalt.
Buried alluvial deposits are known as deep leads and some people believe there is a fortune in diamonds in the deep lead at Copeton, in the New England district of New South Wales, but the cost of finding out has made it too great a gamble for anyone to venture as yet. Copeton is unique in being the only place in Australia where a diamond has been found in its original volcanic vent. This was a dolerite (basalt) dyke at Oakey Creek. The vast changes that have taken place on the earth’s surface have given rise to two other types of rocks beside those of an igneous nature. Sedimentary rocks are derived from the weathered waste of older rocks, like sandstone or conglomerate, or precipitated from solution, as gypsum or limestone. Gemstones are sometimes found among the pebbles and rock fragments making up conglomerates.
Richer in ores than the water-formed sediments are the metamorphic rocks. These are created by the transformation of igneous and sedimentary rocks under extremes of heat and pressure. Under these circumstances granite become gneiss and limestone changes to marble. This is known as regional or dynamic metamorphism and may occur over large areas. Metamorphic rocks are a product of the tremendous convulsions of the earth’s surface that I have already mentioned. When magma forces its way into and through existing rocks, changes occur that are described as local or contact metamorphism.
In this, the superheated, concentrated solutions of magmatic water, with its chemical mineralisers, play an important part. As a result, sapphires and rubies, garnets and spinels among other gems occur in contact metamorphic deposits.
In some metamorphic rocks, crystals of mica, garnet, chlorite and other minerals have been lined up so that the rock will break easily along parallel surfaces. Such rocks are called schists. Turquoise is found in veins through some schists and slate —metamorphosed shale from Rockhampton to Brisbane in Queensland, and also at localities in New South Wales and Victoria. Among other gemstones produced from silica solutions are chalcedony, agate and Australia’s pride, the opal.
Opal comes in two forms, common and precious; with the common opal, known to the miners as potch, often acting as a signpost to the better stuff. Potch can be colorless, as hyalite, amber, milky, blue-gray or black, but it lacks iridescence and fire. Precious opal glows in red, blues, and greens, colors that flash and move as the stone is turned in the light, rainbow hues created by the breakdown of light through layers in the gem having slightly different refractive properties.
In Australia precious opal was first discovered as nodules and veins in cracks and cavities of basaltic lava and the quartz-rich igneous rocks called andesite or trachyte. But this mountain opal was disappointingly subject to cracking and crazing on exposure to dry air. The real opal country is the 50000 square miles of sandstone laid under the sea that spread over much of central Australia 120 million years ago. This dry and bare expanse of modest hills and sandstone ridges takes in 52 known mining localities in Queensland as well as White Cliffs and Lightning Ridge in New South Wales.
Mines at Andamooka and Coober Pedy are in sandstone and shale of a similar period and it is likely that important deposits of opal await discovery in the so-called desert sandstones of South Australia. The silica solutions which filled crevices and replaced other substances, such as wood and bone, in the rock also cemented the sandstone into what is called duricrust. As angel stone, shin-cracker and steelband, this hard rock is usually found in layers above opal.
A number of fossils have been turned to opals, including plants, shells and the bones of dinosaurs. Just before the First World War an almost perfect skeleton of a small dinosaur came to light at White Cliffs. Part of a crocodile’s jaw and teeth in blue black opal was dug up at Lightning Ridge, where the celebrated ‘nobbies’ are also of fossil origin. But this is not to say that the opal dates back to dinosaurs. The skeleton of a cat, buried in a miner’s hat, was found to have turned to pale pink opal. Gateposts buried 20 years were found to be opalised at the foot.
Where To Look: (continued)
Tuesday, September 11, 2007
Monday, September 10, 2007
Jose Carreras
I think the second to be true, because the soul is the center and the source of all these emotions, it's the start of singing, it's inside us; the voice is the instrument, but it's the brain that gives the orders for our actions, so I strongly believe that singing starts in the soul.
Annie Hall
Greatest Opening Film Lines (Annie Hall - 1977):
There's an old joke: Two elderly women are at a Catskill Mountain resort. And one of 'em says: 'Boy, the food in this place is really terrible.' The other one says: 'Yeah, I know. And such small portions.' Well, that's essentially how I feel about life. Full of loneliness and misery and suffering and unhappiness, and it's all over much too quickly.
There's an old joke: Two elderly women are at a Catskill Mountain resort. And one of 'em says: 'Boy, the food in this place is really terrible.' The other one says: 'Yeah, I know. And such small portions.' Well, that's essentially how I feel about life. Full of loneliness and misery and suffering and unhappiness, and it's all over much too quickly.
Investing: The Last Liberal Art
Good Books: (via Emergic) Robert Hagstrom’s book Investing: The Last Liberal Art talks about the need for a latticework of mental models. It is inspired by Charlie Munger’s thinking that one needs to have a framework of the best ideas across multiple disciplines. I have been a Charlie Munger fan for a long time. So it wasn't difficult for me to understand the concept. It's a good book.
From the book description: Investing: The Last Liberal Art offers a unique picture of investing within the larger world. It explains how investment management works by borrowing the big ideas from other complex disciplines: biology, economics, mathematics, philosophy, physics, and psychology. In the biology chapter, Hagstrom analyzes the central nervous system and the immune system as complex adaptive systems and then draws parallels with the behavior of the economy and the stock market. In the physics chapter, he explores a mathematical distribution and considers the advantages of scale in relation to the bigger is better models that define the business strategies of Wal-Mart, McDonald's, and Home Depot. This interdisciplinary approach or model describes in which mechanisms the markets work and how to select and hold stocks.
Chetan Parikh writes in his review:
This book is certainly the best book that I have read for a long time. It is a book on how to connect and unify many disciplines - physics, biology, social sciences, psychology, philosophy and literature - to investing and the markets. It also contains some serious advice on how to read a book - a boon to avid bookworms like me.
Ideas just bubble from every page - the author warns in the preface: "Reading this book requires, then, both an intellectual curiosity and a significant measure of patience." - I went through the book in just two sittings, impatient as I was for more. In a way, this book crystallises the thoughts of Charlie Munger, Vice-Chairman of Berkshire Hathaway, who believes in a liberal arts understanding of investing and feels that building a latticework of mental models could greatly help people to improve their investment returns. Bill Miller, the investing superstar of Legg Mason, actually practices this by gaining insights from various disciplines to aid his investment thinking.
To be an intellectual Christopher Columbus, an investor should acquire models or concepts from various branches of knowledge and then attempt to recognise patterns of similarity in them. Investment decisions have a higher probability of success when ideas from other disciplines also lead to the same conclusion. As Charlie Munger has stated - "You've got to have models in your head and you've got to array your experience - both vicarious and direct - on this latticework of models." As Benjamin Franklin said it is forming "habits of mind" that seek to link together different disciplines. Intelligence is really a factor of how many connections or links one has learned. As Munger also stated: "You can reach out and grasp the model that better solves the overall problem. All you have to do is know it and develop the right mental habits. Worldly wisdom is mostly very, very simple. There are a relatively small number of disciplines and a relatively small number of truly big ideas. And it's a lot of fun to figure it out. Even better, the fun never stops. Furthermore, there's a lot of money in it, as I can testify from my own personal experience. What I'm urging on you is not that hard to do. And the rewards are awesome. It'll help you in business. It'll help you in law. It'll help you in life. And it'll help you in love. It makes you better able to serve others, it makes you better able to serve yourself, and it makes life more fun."
From the book description: Investing: The Last Liberal Art offers a unique picture of investing within the larger world. It explains how investment management works by borrowing the big ideas from other complex disciplines: biology, economics, mathematics, philosophy, physics, and psychology. In the biology chapter, Hagstrom analyzes the central nervous system and the immune system as complex adaptive systems and then draws parallels with the behavior of the economy and the stock market. In the physics chapter, he explores a mathematical distribution and considers the advantages of scale in relation to the bigger is better models that define the business strategies of Wal-Mart, McDonald's, and Home Depot. This interdisciplinary approach or model describes in which mechanisms the markets work and how to select and hold stocks.
Chetan Parikh writes in his review:
This book is certainly the best book that I have read for a long time. It is a book on how to connect and unify many disciplines - physics, biology, social sciences, psychology, philosophy and literature - to investing and the markets. It also contains some serious advice on how to read a book - a boon to avid bookworms like me.
Ideas just bubble from every page - the author warns in the preface: "Reading this book requires, then, both an intellectual curiosity and a significant measure of patience." - I went through the book in just two sittings, impatient as I was for more. In a way, this book crystallises the thoughts of Charlie Munger, Vice-Chairman of Berkshire Hathaway, who believes in a liberal arts understanding of investing and feels that building a latticework of mental models could greatly help people to improve their investment returns. Bill Miller, the investing superstar of Legg Mason, actually practices this by gaining insights from various disciplines to aid his investment thinking.
To be an intellectual Christopher Columbus, an investor should acquire models or concepts from various branches of knowledge and then attempt to recognise patterns of similarity in them. Investment decisions have a higher probability of success when ideas from other disciplines also lead to the same conclusion. As Charlie Munger has stated - "You've got to have models in your head and you've got to array your experience - both vicarious and direct - on this latticework of models." As Benjamin Franklin said it is forming "habits of mind" that seek to link together different disciplines. Intelligence is really a factor of how many connections or links one has learned. As Munger also stated: "You can reach out and grasp the model that better solves the overall problem. All you have to do is know it and develop the right mental habits. Worldly wisdom is mostly very, very simple. There are a relatively small number of disciplines and a relatively small number of truly big ideas. And it's a lot of fun to figure it out. Even better, the fun never stops. Furthermore, there's a lot of money in it, as I can testify from my own personal experience. What I'm urging on you is not that hard to do. And the rewards are awesome. It'll help you in business. It'll help you in law. It'll help you in life. And it'll help you in love. It makes you better able to serve others, it makes you better able to serve yourself, and it makes life more fun."
The EC’s SoC Predicament: Is The Secondary Market A Relevant Market?
Chaim Even-Zohar writes about primary and secondary vs. rough diamond markets + the future of secondary rough diamond markets + other viewpoints @ http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=23540
How To Talk To An Artist
Gail Gregg provides useful tips on interacting with artists + other viewpoints @ http://artnews.com/issues/article.asp?art_id=1856
Where To Look
Bill James (Australia) writes:
The geologist is a man with a bunch of keys to nature’s jewel box. But there are many different keys for the box has many locks and most of them are hidden under the dust of ages. The written history of even the oldest and most celebrated jewels is only an infinitesimal part of their story. Their strangest adventures in the world of men are insignificant compared to the wonder of their creation.
Nearly all gemstones are minerals, some of which are rarer than others. This rarity is one of the qualities for which they are prized, for only a minor proportion of all the world’s gemstones exist in localities where they can be readily collected or mined. It is in reading the clues to these localities that the science of geology comes to the aid of gem seeker. It is as if nature had set up a great game of treasure trove for us with gemstones as one of the prizes.
If we were lucky, we may stumble upon a gem deposit by accident. But the odds of doing so are more on our side if we have an idea where to look. Like other minerals, most , but not all, gemstones were formed in association with igneous rocks. Igneous means formed by heat, and these are rocks which resulted from the cooling and solidifying of some of the molten matter making up the interior of the earth.
Many igneous rock are said to be of a crystalline texture. This means that their hard mass is composed of small crystals, the size of which is determined by the length of time it took the rock to cool. Other igneous rocks, such as obsidian, are glassy. According to the conditions under which cooling took place, igneous rocks are classed as either extrusive or intrusive. In other words, they either overflowed the existing surface or spread out beneath it.
Basalt is a typical extrusive rock. It is fine-grained because it cooled quickly on the surface. Granite is an intrusive or plutonic rock. Its texture is coarser than that of basalt because it cooled more slowly underground. At the depth of 40 miles inside the earth there are pockets of molten rock. In conditions of intense heat and pressure, these rocks stew up a superheated mineral soup known to geologists as magma.This magma tends to rise. If it succeeds in escaping through the earth’s crust by means of a volcano, it becomes lava. Otherwise it forms vast, dome-shaped subterranean masses of intrusive rock that are called batholiths and laccoliths according to their shape and size.
In the bygone ages, when the face of the world as we know it was taking shape, batholiths formed the roots and kernel of many high mountain ranges. The surface of a granite batholith many miles in area is exposed around Bathurst, New South Wales, Australia. Nowadays when a geologist finds granite or gabbro or any other intrusive rock on the surface, he knows that the forces of erosion have worn away the material that once covered it. He also knows that there is the possibility of ore deposits and gemstones not far away.
When the original batholith was formed, the magma also spread into cracks and fissures of the surrounding rocks. Geologists call the result a dyke. Because it is in conditions different from the parent magma, the material in the dyke becomes a different substance called a pegmatite. This very coarse-grained rock is one of the sources of ores and gemstones which occur as crystals of various shapes.
Owing to the intense pressures in which it is contained, the magma holds quantities of water, chlorine, fluorine and boron in superheated solutions. These substances are known as mineralisers. The mineralisers help to keep the magma liquid and allow a longer period in which the mineral crystals can grow. Sometimes the crystals attain great size. Beryl crystals up to several tons in weight have been mined from pegmatite dykes at Broken Hill, New South Wales, Australia.
Emeralds, aquamarines, topaz, tourmaline, zircon and large crystals of cassiterite (tinstone) are all found in pegmatite dykes. So is quartz in various crystalline forms. But not every dyke holds gemstones. It is one of the elements of nature’s hide-and-seek game than an exact combination of chemicals must be present at the right temperature. Most precious stones owe their value to microscopic traces of metallic compounds.
Quartz is sometimes injected into the surrounding rocks by itself as vein quartz. Sometimes, combined with ores of gold or other metals, it is in ‘pipes’. Cavities known to miners as vughs (pronounced ‘vuggs’) occur in the pipes. In these vughs, crystals of the various types of quartz gemstones grow from concentrated silica solutions. These also reach large size and one of the finest recorded in Australia was a 25 lb. rock crystal mined at Kingsgate, near Oban, in New England.
It takes a long time to grow a crystal of this size but it is nothing compared to the immense period over which nature has produced our gemstone resources. The oldest rocks in Australia, occurring in the south-west, date back at least 2000 million years. The forces that create gemstones were already in action then. At that time the earth’s crust was more subject to movement and change than it is now. It was an era of incredible violence. The rocks warped, buckled and broke, spewing out streams of glowing lava under skies darkened by incessant floods of rain and lurid with the smoke and flame of volcanoes. Monstrous upheavals and descents took place over large areas. During the last 1000 million years the Australian continent was split into islands several times by the movement of rocks.
About 135 million years ago, the highlands of the Queensland coast between Cape Melville and Rockhampton were parted from the rest of the continent as it is now. The sea also divided New South Wales and Victoria from Western Australia at this time. During Australia’s geological history there were at least nine periods of tremendous subterranean activity when rocks warped and folded and great batholiths formed. The first and second of these periods took place between 2000 million and 500 million years ago. Six times more the continent was reshaped over the next 300 million years, with the final episode occurring around 75 million years ago.
Most of Australia’s gemstone deposits trace to one or other of these periods. We can pick up stones that are older than the dinosaurs, stones that have endured while mountains higher than Kosciusko have risen and been washed away. Against the dramatics of earthquake and volcanic eruption, the steady stealthy activity of wind and rain, ice and running water has little impact. Nevertheless, these are the forces that have done more than anything else to shape the face of the land.
Where To Look: (continued)
The geologist is a man with a bunch of keys to nature’s jewel box. But there are many different keys for the box has many locks and most of them are hidden under the dust of ages. The written history of even the oldest and most celebrated jewels is only an infinitesimal part of their story. Their strangest adventures in the world of men are insignificant compared to the wonder of their creation.
Nearly all gemstones are minerals, some of which are rarer than others. This rarity is one of the qualities for which they are prized, for only a minor proportion of all the world’s gemstones exist in localities where they can be readily collected or mined. It is in reading the clues to these localities that the science of geology comes to the aid of gem seeker. It is as if nature had set up a great game of treasure trove for us with gemstones as one of the prizes.
If we were lucky, we may stumble upon a gem deposit by accident. But the odds of doing so are more on our side if we have an idea where to look. Like other minerals, most , but not all, gemstones were formed in association with igneous rocks. Igneous means formed by heat, and these are rocks which resulted from the cooling and solidifying of some of the molten matter making up the interior of the earth.
Many igneous rock are said to be of a crystalline texture. This means that their hard mass is composed of small crystals, the size of which is determined by the length of time it took the rock to cool. Other igneous rocks, such as obsidian, are glassy. According to the conditions under which cooling took place, igneous rocks are classed as either extrusive or intrusive. In other words, they either overflowed the existing surface or spread out beneath it.
Basalt is a typical extrusive rock. It is fine-grained because it cooled quickly on the surface. Granite is an intrusive or plutonic rock. Its texture is coarser than that of basalt because it cooled more slowly underground. At the depth of 40 miles inside the earth there are pockets of molten rock. In conditions of intense heat and pressure, these rocks stew up a superheated mineral soup known to geologists as magma.This magma tends to rise. If it succeeds in escaping through the earth’s crust by means of a volcano, it becomes lava. Otherwise it forms vast, dome-shaped subterranean masses of intrusive rock that are called batholiths and laccoliths according to their shape and size.
In the bygone ages, when the face of the world as we know it was taking shape, batholiths formed the roots and kernel of many high mountain ranges. The surface of a granite batholith many miles in area is exposed around Bathurst, New South Wales, Australia. Nowadays when a geologist finds granite or gabbro or any other intrusive rock on the surface, he knows that the forces of erosion have worn away the material that once covered it. He also knows that there is the possibility of ore deposits and gemstones not far away.
When the original batholith was formed, the magma also spread into cracks and fissures of the surrounding rocks. Geologists call the result a dyke. Because it is in conditions different from the parent magma, the material in the dyke becomes a different substance called a pegmatite. This very coarse-grained rock is one of the sources of ores and gemstones which occur as crystals of various shapes.
Owing to the intense pressures in which it is contained, the magma holds quantities of water, chlorine, fluorine and boron in superheated solutions. These substances are known as mineralisers. The mineralisers help to keep the magma liquid and allow a longer period in which the mineral crystals can grow. Sometimes the crystals attain great size. Beryl crystals up to several tons in weight have been mined from pegmatite dykes at Broken Hill, New South Wales, Australia.
Emeralds, aquamarines, topaz, tourmaline, zircon and large crystals of cassiterite (tinstone) are all found in pegmatite dykes. So is quartz in various crystalline forms. But not every dyke holds gemstones. It is one of the elements of nature’s hide-and-seek game than an exact combination of chemicals must be present at the right temperature. Most precious stones owe their value to microscopic traces of metallic compounds.
Quartz is sometimes injected into the surrounding rocks by itself as vein quartz. Sometimes, combined with ores of gold or other metals, it is in ‘pipes’. Cavities known to miners as vughs (pronounced ‘vuggs’) occur in the pipes. In these vughs, crystals of the various types of quartz gemstones grow from concentrated silica solutions. These also reach large size and one of the finest recorded in Australia was a 25 lb. rock crystal mined at Kingsgate, near Oban, in New England.
It takes a long time to grow a crystal of this size but it is nothing compared to the immense period over which nature has produced our gemstone resources. The oldest rocks in Australia, occurring in the south-west, date back at least 2000 million years. The forces that create gemstones were already in action then. At that time the earth’s crust was more subject to movement and change than it is now. It was an era of incredible violence. The rocks warped, buckled and broke, spewing out streams of glowing lava under skies darkened by incessant floods of rain and lurid with the smoke and flame of volcanoes. Monstrous upheavals and descents took place over large areas. During the last 1000 million years the Australian continent was split into islands several times by the movement of rocks.
About 135 million years ago, the highlands of the Queensland coast between Cape Melville and Rockhampton were parted from the rest of the continent as it is now. The sea also divided New South Wales and Victoria from Western Australia at this time. During Australia’s geological history there were at least nine periods of tremendous subterranean activity when rocks warped and folded and great batholiths formed. The first and second of these periods took place between 2000 million and 500 million years ago. Six times more the continent was reshaped over the next 300 million years, with the final episode occurring around 75 million years ago.
Most of Australia’s gemstone deposits trace to one or other of these periods. We can pick up stones that are older than the dinosaurs, stones that have endured while mountains higher than Kosciusko have risen and been washed away. Against the dramatics of earthquake and volcanic eruption, the steady stealthy activity of wind and rain, ice and running water has little impact. Nevertheless, these are the forces that have done more than anything else to shape the face of the land.
Where To Look: (continued)
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