Treasure Maps

Bill James (Australia) writes:

Most often used by rock-hounds is the inch to a mile scale military map, prepared by the Royal Australian Survey Corps and available from stationers and booksellers. This map gives accurate and detailed information on routes and camping places as well as indicating promising prospecting localities.

The military map is most useful in conjunction with one of the detailed geological maps produced by the Commonwealth Bureau of Mineral Resources or the Mines Department of the various States. When planning a prospecting trip, it is wise to have several alternatives in mind, so as to avoid disappointment. In a granite area, for instance, we may wish to try our luck on the rockface and talus, on mine dumps and also at what we work out as the most promising stretch of the river.

We require a good deal of equipment to tackle the rockface. A pick and showel, a light mineralogist’s pick-hammer, a striking hammer of about 3lb weight—one with a square face and a chisel peen is the most useful—and half-a-dozen rock gads of various sizes. A steel crowbar or prybar of the type known to American rockhounds as a pocket robber is invaluable. This tool, which varies from 18 in. to 45 in. according to taste, has a 30 degree bend at each end to provide powerful leverage.

A sledgehammer up to about 14 lb in weight may also be needed. The rockface offers three collecting areas—the face itself, the talus, and the eluvial deposits buried beneath the talus which have been concentrated by gravity. Both the last-named present few problems except hard pick and showel work, cracking any lumps of rock that look as if they could contain crystals. A quarter or eighth-inch sieve will be required to deal with the smaller gravel.

The rockface is another matter. Weathered rock can be a deathtrap even to a properly equipped and experienced climber. But you are neither experienced nor properly equipped. If the face is in any way difficult, you will be a fool try climbing and working on it. Leave it alone and concentrate on the easier stuff. That goes for quarries too, but there the owner will probably insist that you remain on terra firma, anyway.

It may happen that a pegmatite dyke or sill or a rock cavity occurs in a position where you can attack it safely. The finest gem crystals are often found in gas holes of pink or red granites and plants growing out of the rockface may indicate such a cavity.

In basalts, the steamholes or amygdales may be filled with opal or agate. Amethysts are found in quartz veins as a druse—a cavity lined with crystals of the same nature as the host rock, as distinct from a geode. Gem pockets are usually found in the midst of the thickest part of pegmatite dykes and sills. The rock should be tested at these points with the pick and will be found to break open comparatively easily over a pocket of crystals.

Cavities in the rock mostly have to be opened by splitting with a succession of gads and the prybar then used carefully to break off and bring out the crystals. Sometimes these cavities are filled with clay and the contents must be sieved to make sure no gems are lost.

Sieves, a bucket and shovel, with maybe a pick and a crowbar to shift the boulders are what we require to deal with river gravels. Some people use a miner’s pan but the best equipment for gemstones is two sieves which fit together. I prefer the half-inch and quarter-inch mesh in general, but a quarter-inch sieve and an eight-inch or even a one-sixteenth-inch are better if there is any chance of picking up diamonds.

Standing gumboot deep in a river agitating a couple of sieves becomes hard work very quickly. However, special aluminum sieves are now available to lighten the load for rockhounds. It is no use looking for gem gravels on the steep slopes where the river runs swiftly most of the time and torrentially in heavy rain. But as soon as the surface becomes more level or some obstruction checks the flow, the heavier part of the gravels will be discarded.

Deposits are formed on the inside of bends and on the downstream side of obstructions. Any gutters, hollows and crevices in the streambed become natural traps for gemstones. Boulders trundled along the river by floods pin down the gravels wherever they come to rest. Any gravel bar or dump of tailings from an alluvial dredge is worth a try on a river known to contain gemstones. The method is to fit the two sieves together with the wider mesh on top and then fill the upper sieve with gravel. Dip both sieves in the river so that the water covers the gravel and rotate to and fro vigorously. Continue this action until all the finer material has dropped into the lower sieve.

Carefully go over the pebbles remaining in the top sieve for any gem material before emptying it. Then take the lower sieve, immerse it until the gravel is just below water level and agitate thoroughly once more. The object is to bring all the heavier material, including gemstones, to the bottom of the sieve. Give the sieve a final to-and-fro jerk, take it smartly from the water and turn it over on the nearest handy piece of flat ground.

Treasure Maps: (continued)

Gemstones With Change Of Color

To anyone who has ever viewed a fine quality piece of alexandrite, the phenomena of change of color must certainly rank among the greatest wonders of the gem kingdom. Change of color or the alexandrite effect as it is known is a relatively recent discovery. The gem was christened alexandrite, in honor of the future Czar Alexander II on whose birthday it was supposedly found. After its discovery it achieved rapid popularity, not only for its interesting color change, but also because the two colors, green and red, were the colors of the Czarist Russian army. Fine quality alexandrites are today among the most desirable precious stones. Besides the normal criteria for judging gems, the quality of an alexandrite is based primarily on the quality of color change and the intensity and purity of those colors. The best colors would those of a fine emerald or ruby and this stone would be described as having a one hundred percent change. Stones of this quality may be difficult to find, but most specimens show a change of only twenty to thirty percent with the two colors being diluted with brown and yellow.

There are various gemstones which display the phenomenon of change of color. Synthetic alexandrite has been manufactured in Russia, USA and other countries by flux and Czochralski (pulling) process. Both types display a fine change from bluish green to purplish red, just as in the natural stones. The flux grown gem materials show inclusions such as wispy flux fingerprints, platinum plates and crystals and angular zoning. Stones grown by the Czochralski process are usually free of inclusions, but may show gas bubbles and/or curved growth lines.

Of all the gem materials which show a change of color, none is more commonly seen than the synthetic color change (alexandrite-like) sapphire. This material is not synthetic chrysoberyl, but instead is flame fusion synthetic corundum. By adding a trace of vanadium to the growth mixture, a color change is produced. The color is grayish green in daylight and purplish red in incandescent light. Often this gem will be offered for sale as synthetic alexandrite or even worse, as natural alexandrite. The stone is not difficult to identify as the color change is not exactly the same as true alexandrites. Proper examination will reveal curved striae and possibly gas bubbles. Natural color change sapphires do exist and show a change that varies from violetish blue to grayish green in daylight, to purplish red in incandescent light. The change of color can be attributed to vanadium, chromium, iron and titanium in various proportions. Fine quality color change sapphires are prized by collectors.

Next to alexandrite, the stone with the most dramatic change of color is probably the color change garnet. Color change garnets show a change very similar to that of alexandrite from a bluish green to purplish red. Glass imitations have been made to simulate a color change as well. Since the stone does not really change color from one light source to another it should not considered as a true change of color.

Gems From New South Wales, Australia

It has been reported that there at least seven alluvial sapphire localities producing pink, red and purple corundums + blue, yellow and green corundums at Barrington Tops, Macquarie River, Cudgegong River, Swan Brook, Bingara, Tumbarumba and Yarrowitch Valley. The samples specimens may be useful to study the unique chemisty + origin of ruby and sapphire deposits and their economic significance in New South Wales, Australia.

Frank Capra

Film is one of the three universal languages, the other two: mathematics and music.

A Case Study: VNU As Its Competitor’s Best Promoter

Chaim Even-Zohar writes about media conglomerates' operating system (s) + the impact when bad decisions are made by their managers + other viewpoints @ http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=24470

My dealer, Saint And Sinner

The Economist profiles the Wildensteins + the powerful dealers of the art world + other viewpoints @ http://www.economist.com/daily/columns/artview/displaystory.cfm?story_id=9748579

Treasure Maps

Bill James (Australia) writes:

An up-to-date survey map offers rock hounds as many clues to buried treasure as any pirate chart of the Spanish Main ever did.

Contour lines make up the bulk of clues. These lines indicate the rise and fall of the land surfaces by connecting points at the same level and thus outline the shapes of hills and valleys as seen from above. The lines are drawn at regular intervals and distance between them indicates the steepness of the slope. Where the lines are spaced evenly, the land is rising gradually. Where they bunch together, the rise is abrupt, as on a cliff face.

Other details are shown by symbols explained in the margin of the map. Tiny green sketches represent scattered woodland, green patches shows the heavier bush and rivers appear as wavy blue lines. Creeks which only flow in wet weather are shown in broken blue lines. Careful study of this map tells the gem seeker where he is likely to find bare rocks above talus slopes littered with fragments from the weathered face and also the places to which streams and rivers have carried debris from the rocks.

We can trace the pattern of blue lines on the hillside where a multitude of trickles feed a brook and a multitude of brooks feed a river. Study of this drainage system shows how gemstones are gathered from thousands of acres of hillside. Checking the course of the river against contours shown on the map discloses the places where the current slows down and the gem gravels pile up.

Obviously a river cannot collect gemstones unless it flows among gem-bearing rocks. To identify rocks, the survey map must be compared against a geological map of the area. On the geological map, the rocks occurring beneath the soil level are picked out in contrasting colors and named.

If the rocks of the area are granite, there is a good chance of finding beryl, feldspar, topaz, tourmaline and gem varieties of quartz. Basalt and volcanic tuffs may contain chalcedony, opal, jasper and agate, both in the form of seams and thunder eggs. Gneiss, schists and marbles yield sapphire, garnets, spinel and zircon.

But that is not to say that rocks of any given variety must necessarily be gem-bearing. Some granites, for instance, produce no gems, but in that case the survey map again provides a clue. Strong mineralized granites are the ones which becomes weathered most quickly, forming smoothly rounded hills, well covered with the trees and bushes marked on the map.

Pale streaks of quartz veins or quartz floaters may be visible on such granites. Pegmatites may outcrop, showing glittering mica surfaces in the sunshine, or rock crystals peep among the grass roots to pinpoint a pocket of gemstones.

Almost certainly the survey map will show mines in the vicinity—mines for wolfram, or tin, or silver-lead, or any one of half-a-dozen other minerals. Given permission by the owners, fossicking on mullock heaps of mines and quarries can be a rich source of gem materials.

Treasure Map: (continued)

Specialty Glasses

Aventurine Glass is man-made paste with the addition of fine copper spangles. The reddish brown variety is sometimes met with under the name gold stone or gold star stone. Spangled-aventurine-effect is due to triangular or hexagonal scales of copper. The blue variety (lapis imitation) is colored by cobalt and will appear red under the Chelsea Color Filter.

Slocum Stone is a recent (1976) opal imitation named after its Canadian inventor. It is a composite paste, probably consisting of a body of crown glass of low R.I. (about 1.52) and melting point, into which are pressed fragments of thin films of blown glass of differing R.I. Colors are probably due to interference between layers of differing R.I. The diagnostic features are flow lines and bubbles distorted by pressure during manufacture. Slocum stone triplets are now on the market as well. Slocum stone has been marketed under the deceptive name 'Opal Essence'. Slocum stone can be an extraordinarily good opal simulant. It is reported that the results of production can vary from batch to batch. Some stones display pinfire-type play of color; others may show much broader triangular flashes of color. The background may be black, translucent or nearly completely transparent like fine crystal opal. Low power magnification under the gemological microscope will reveal the twisted tinsel-like nature of the color flashes.

Rhinestone refers to transparent paste which, colorless in the main, shows patches of various colors. Most specimens consist of a thin metallic film which has been vacuum-sputtered onto the surface of the glass thereby causing iridescence.

Imori Glass or Meta Jade is a partially devitrified, translucent green glass produced by Imori in Japan. Slow cooling cause partial crystallization, which often appears as a dendritic (fern-like or tree-like) structure under magnification. The stones may show gas bubbles.

In some cases asterism is obtained by engraving fine, intersecting lines, or by impressing three sets of intersecting lines, on the back of a cabochon. The stones then are frequently backed by colored foil to lend color and increase reflectivity. On the other hand, cat's-eye-like effects can be obtained by the incorporation of parallel glass fibers or by the elongation of included bubbles.

John Huston

You walk through a series of arches, so to speak, and then, presently, at the end of a corridor, a door opens and you see backward through time, and you feel the flow of time, and realize you are only part of a great nameless procession.

Better Presentations

Good Books: (via Emergic) Cliff Atkinson book Beyond Bullet Points: Using Microsoft PowerPoint to Create Presentations That Inform, Motivate, and Inspire. is about how to improve presentations using PowerPoint. I thoroughly enjoyed the book and reviews. I really learned a lot.

Here is one of Cliff Atkinson’s blog posts entitled Center of Gravity:
Whenever I look at a PowerPoint presentation for the first time, I go to Slide Sorter view to get the lay of the land: Can I see a clear story across the entire experience? Then I'll shift to Notes Page view: Are the projected visuals and spoken words planned together? And last I'll go to Normal view: Can I easily understand the main idea of this slide?

It's usually the case that the answer is No to all three questions. More often than not, the presentations are very difficult to understand, packed with more text and data than anyone's cognitive ability can process; and little if any narrative structure. What I commonly find is that any single presentation is actually multiple presentations that are yearning to be liberated. Where we might try to load up the slides to save time by creating a one-size-fits-all presentation, we actually end up with a situation where one-size-confuses-all. One solution to the problem is the discipline of completing Act I of your story template. When you write the statements that form the headlines of the first five slides, you are making purposeful decisions that will sort, distill and structure information in a way that makes sense to your specific audience.

Franz Dill of IFTF Future Now writes:
Atkinson's approach is very nicely tailored for important, complex presentations. His model is that of telling a story ... storyboard it, use minimal text (no bullets), engage the audience. He picks a board presentation scenario and goes through it in some detail. Very thoughtfully done. I also like the fact that he covers other parts of the process ... how you present the slides, pacing, and how to tailor it for later emailing to people that could not attend, now a very common situation. I have been saving presentations for reference for some time, and am often amazed at how incomprehensible a slideshow can become. In fact the latter situation has often made me use more text and slide detail than I would otherwise.

Lars Bergstrom adds in a review on Amazon: I believe that the book's greater contribution is pointing out that most people structure presentations as a dump of data rather than taking into account their audience and the goal of their presentation -- why are people there? What do you want them to do or believe after you're done presenting? Even if you disagree with Cliff's convincing points on removing bullets from your decks, you should take to heart his framework for developing concepts and decks.

Cliff Atkinson said in an interview with Management Consulting News:
When we start talking about text on a slide, it’s important to begin by affirming the research: presenting text that is identical to narration actually harms the ability of the audience to understand. Removing the text from the screen improves the ability of the audience to retain the information by 28%, and improves their ability to apply the information by 79%. Keeping in mind the imperative to minimize text on the screen, the bulk of writing text for a PowerPoint presentation should be in the headlines that form your story structure. Then you write the narrative explanation of each of those headlines in Notes Page view. Because the words have already been captured in the form of the headlines and notes, the screen is much less dependent on text to convey information and more dependent on you to communicate it with your spoken words and expressions. With this approach, the PowerPoint screen becomes a much more creative and interesting tool that can hold a few words, or no words at all.

Dave Pollard has an excellent analysis of the process:
What this book does is provide a process to supply the pictures to go along with the story, so your presentation becomes "a blend of movie and live performance". The process has three steps: Writing a script to focus your ideas, storyboarding the script to clarify the ideas, and producing the script to engage the audience. My previous posts have told you about the art of crafting a good story. The storyboard for a movie script is actually sketches of visuals, but for purposes of this book it's merely parsing of the critical parts of the story onto successive slides. Then you use graphics -- and few words -- to reinforce the key points of the story with memorable images.

Provocateurs, Ghosts, Accomplices, And Starz

Konstantin Akinsha writes about the Moscow Biennale of Contemporary Art + interest (s) in Russian art circles about new ideas, concepts and interpretations + other viewpoints @ http://artnews.com/issues/article.asp?art_id=1821

Hidden Glory

I liked the poem because of the inspiring note + the passion factor.

It is a feeling that Mr and Mrs Fred Richards, of Murrarie, Brisbane, Australia expressed very clearly in the poem in stone which they dedicated to Mr Gan Timur because of his love for agate.

The verse was written by Mrs Edna Richards in praise of Queensland’s beautiful rainbow agate. She calls it ‘Hidden Glory’ and it reads:

A man picked up a stone one day,
While walking beside a stream;
He looked at it, then threw it away,
It chipped and lo! a gleam.
He took it home and studied it,
And saw to his surprise,
That beauty lay beneath its crust;
It was indeed a prize.
When cut through with a diamond saw
A picture did unfold
Of hills and dales, red sunset, too,
A glory to behold.
So, whenever you see an ugly stone,
Don’t pass it by with scorn;
It may contain a treasure trove
Just waiting to be born.

These words now glitter in a panel of blue and gold at the Richard’s home. Each of the 478 letters has been cut and polished from one of a score of different Australian rocks and gemstones. It was a labor of love that took Fred Richards 300 hours. The result combines jasper, agate, chrysoprase, prase, trachyte, rhyolite, petrified wood, common opal, obsidian, onyx, grass stone, aventurine quartz, blue sodalite, tourmaline, rock crystal, amethyst, pitchstone and granite.

What Makes A Painting A Painting?

Linda Yablonsky writes about new interpretations of painting by the experts, and artists of all colors and disguises + the hybrid, the crossover, the many-splendored concepts in the art arena + other viewpoints @ http://artnews.com/issues/article.asp?art_id=1824

A Gem Miner's Tip

The golden rule on mine dumps is to look for the spots where the grass and weeds are growing undisturbed. Those are the best places to search for gems.

Life’s A Gamble, But Worth The Risk

I think Bob is right. It's a unique reflection when you realize how impermanent our world is. A minute you are Mr Somebody, and the next minute you're gone.

(via NationMultimedia) Bob Kimmins writes:

As you drive to work every morning, are you aware that your chance of dying in a crash is 84 to 1? This means that anyone placing a Bt 100 bet on that untimely end would stand to win Bt 8400. Life is a gamble, and everything we do involves some sort of risk, from high-chance favorites such as road accidents and disease to long shots like choking on a banana.

And I wonder what the odds would have been in 1923 when jockey Frank Hayes died of a heart attack during a horserace, with his mount, Sweet Kiss, finishing first and Hayes still in the saddle. Perhaps it’s uncertainty in life that leads people into gambling—a subconscious effort to overcome fate. Anthropologists agree that gambling was in evidence 4000 years ago in China, India, Egypt and Rome. Dice dating back to 1500 BC were found in Thebes, and related writing were discovered on tablets in the Pyramid of Cheops. Thailand, too, has a rich history of gambling.

More than 1000 years ago, bean guessing was probably the earliest game of chance in the Land of Smiles, and in the 1800s King Rama III legalized gambling to generate tax revenue. That decision led to widespread debt and bankruptcy and increased crime, however, so King Rama V outlawed it again.

In a turnabout decision, just after World War II, the Finance Ministry became responsible for running legal casinos—only for the well to do. But the law was flouted by allowing all comers to play, and the resulting debts and decline in social values prompted the ultimate clampdown.

Robert Redford

I can't think of anything outside of having the gift yourself and creating yourself. I can't think of the next better thing to do than being able to put it back. Creative expression, I think, is vital to the success of any society. ... A society without art will die.

Less Troubled Waters

The Economist writes about detergents that can be switched on and off, a new spin-off in chemistry with wide applications + other viewpoints @ http://www.economist.com/science/tq/displaystory.cfm?story_id=9677960

It would be interesting to explore how it works in gemstone cleaning + treatments in the future.

Cultured Pearl Terminology

There are many interpretations on cultured pearl (s) terminology in the industry.

(via Gems & Gemology) According to H A Hanni, a leading expert in gemology, all cultured pearls are tissue nucleated.

The terms bead nucleated and tissue nucleated are often used. The combination of these two terms creates the idea that a cultured pearl is nucleated with either a bead or a piece of mantle tissue, and the term nucleation suggests that there is something in the center of the cultured pearl, either a bead or tissue graft. However, the former does not lead to a cultured pearl if no tissue is added.

And, since all cultured pearls start with a piece of mantle tissue, this expression does not adequately differentiate between the two types. It is thus confusing and of no use. Further, the term tissue nucleated causes people to think that the grafted tissue is in the cultured pearl. However, research has indicated that tissue cells from the transplant become part of the pearl sac and do not remain as a residue in the center of the pearl. They do not form a nucleus. The X-ray visible dark structure in the center of these cultured pearls is often a void and preliminary precipitation from the growing surface of what will become the pearl sac. The transplanted mantle-tissue cells that produce the nacre grow into a pearl sac by multiple cell division, making a small pocket. This pocket produces an initial crust of a CaCO3 on its inner surface, but this crust does not completely fill the space, leading to the cavity in the center of a beadless cultured pearl.

H A Hanni proposed the following suggestions to CIBJO commission:
- Omission of the terms nucleus, nucleation, bead nucleated, tissue nucleated.
- Use of the term grafting for the introduction of mantle-tissue cells (with or without a bead).
- Use of the term beading for the introduction of a material that gives the shape to the pearl sac (to grow or already present), regardless of the shape of that bead.
- Use of the terms beaded-cultured pearl and non-beaded (beadless) cultured pearl for the resulting products.

CIBJO have included the above proposals for their Pearl Book.

The New Serenity

Steven Litt writes about the incredible visual experience created by architects + the cultural expressions and financial opportunities + other viewpoints @ http://artnews.com/issues/article.asp?art_id=1696

India’s Import Duty Exemption: Curse Or Blessing?

Chaim Even-Zohar writes about the Indian diamond industry + the tax methodology + other viewpoints @ http://www.idexonline.com/portal_FullEditorial.asp