
	Where results make sense

Topic: Asterism (gemmology)

In the News (Fri 27 Nov 09)

Northern Trust

Marvin Harrison

Peter Chernin

Gary Locke

Match Play

Penelope Cruz

Mickey Rourke

AR Rahman

Danny Boyle

Hugh Jackman

	Asterism
		In gemmology, an asterism is an optical phenomenon displayed by some rubies, sapphires, and other gems of an enhanced reflective area in the shape of a "star" on the surface of a cabochon cut from the stone.
		Asterism is caused by dense inclusions of tiny, parallel, slender fibers in the mineral which cause the light to reflect a billowy, star-like formation of concentrated light which moves around when the mineral is rotated.
		This is usually caused by small needles of rutile (titanium oxide) in the case of ruby and sapphire.
	www.guajara.com /wiki/en/wikipedia/a/as/asterism.html (257 words)

	asterism (Site not responding. Last check: 2007-10-08)
		Asterisms are sub- or supersets of constellations which build a constellation itself, or a group of stars, physically related or not.
		Asterism is caused by dense inclusions of tiny, parallel, slender, fibers in the mineral which cause the light to reflect in such an interesting manner.
		Asterisms are considered to be distinct from constellations, although the origin of most constellations is also a recognizable pattern of stars.
	www.vocamania.com /asterism.aspx (783 words)

	GZ Journal - Technical support Stones 03
		According to McClure and Koivula, the new type of synthetic asterism is created by orientated series of scratches on the surfaces of the precious gems, cut as cabochon, in which the scratches run parallel to each other.
		Although details of the treatment method are as yet unknown, it is assumed that the scratches are applied to the surface of the cabochon by hand, whereby the number of series of parallel scratches defines the number of arms in the synthetic stars.
		The asterism observed in this stone consists of a six-armed star, whereby the pattern and symmetry of the six arms of the star is homogeneous with the triangular symmetry of tourmaline.
	www.gz-journal.de /Techical_support_Stones_03.cfm (1492 words)

	Precious Stones,Precious Gem Stones,Precious Stones Wholesale,Precious Gem Stones Suppliers
		Asterism An optical phenomenon characteristic of starstones when cut en cabochon, producing a six-rayed star shape within the stone.
		It is essential to determine the natural cleavage planes, for if these are not followed the whole stone may shatter into fragments.
		Colour In gemmology, colour is of prime importance.
	www.semi-precious-stone.com /the-professional-terminology.html (1574 words)

	Asterism on a Green Stone?
		Asterism in emerald is apparently not unheard of, but I have never seen one or even a picture of one...chatoyancy (cat's eye) is, of course, not common but better known.
		Asterism begins when 2 lines cross each other.
		Asterism also occurs now and then in the "rhodolite" pyrope-almandines from Africa and probably other garnet types that have properly-oriented rutile inclusions.
	www.pricescope.com /idealbb/view.asp?topicID=12915 (2805 words)

	Sapphires
		The tell-tale sign of synthetic sapphires is the crystalline growth lines which are usually curved due to the pulling during the accelerated crystal growth process.
		Although natural sapphires can show an asterism, the shape of the star is usually somewhat irregular and sometimes indistinct.
		A manufactured star sapphire called the Linde Star shows a very regularly-shaped and distinct asterism because the formation process is more tightly controlled than the natural version.
	www.breadlike.com /pages7/76/sapphires.html (1126 words)

	Wikinfo \| Asterism (Site not responding. Last check: 2007-10-08)
		In astronomy, an asterism is a pattern of stars seen in Earth's sky which is not an official constellation, such as The Big Dipper in Ursa Major or The Teapot in Sagittarius.
		In typography, a rare symbol consisting of three asterisks placed in a triangle, used to call attention to a passage.
		Images, some of which are used under the doctrine of Fair use or used with permission, may not be available.
	www.wikinfo.org /wiki.php?title=Asterism (345 words)

	Gemmology II
		Importance in gemmology, diamond fashioning and lapidary work.
		Types of heavy liquids commonly used in gemmology.
		Students must bring a 10x magnifying glass and a pair of tweezers with a relatively fine point.
	www.ub.es /escgem/curs2-an.htm (196 words)

	SSEF - Publications
		The asterism of this specimen is due to a combination of a six-rayed star emerald and an emerald cat's-eye.
		Three causes for six-rayed stars in various members of the beryl family are known: (a) needle-like mineral inclusions, (b) elongated thin fluid films and (c) elongated negative crystals.
		Asterism is caused by a dense network of rutile needles that are orientated parallel to the three-folg axes of the cubic garnet hosts.
	www.ssef.ch /en/news/publications.html (4644 words)

	Asterism (gemmology) - Wikipedia, the free encyclopedia
		Epiasterism, such as that seen in sapphire and most other gems, is the result of a reflection of light on parallel arranged inclusions inside the gemstone.
		In order to see this effect, the stone must be illuminated from behind.
		Gemmology Education: Gemological Institute of America - London
	en.wikipedia.org /wiki/Asterism_(gemmology) (294 words)

	Gemology World - Can. Institute of Gemmology
		For those trained in gemmology, this is a splendid opportunity to test your knowledge where it counts.
		Visual gemmology will separate the two immediately: Look through the table facet with the CLEAN stone pressed as closely to your eye as possible, aiming at your illuminated penlight.
		Similar coloured tourmaline may be found, but by viewing daylight through the table facet (light colour), followed by viewing through girdle (dark) you will instantly note the difference that identifies this stone.
	www.cigem.ca /416.html (7065 words)

	GZ Journal - Translation December 2001 Gemmology (Site not responding. Last check: 2007-10-08)
		In this case it is a method of synthetically creating asterism in natural materials, cut as cabochon.
		124–128) now describes precious gem minerals with synthetic asterism, although the gems themselves do not produce star stones naturally: sinhalite, cassiterite and samarskite.
		Synthetic asterism is also described for minerals, which have produced natural star stones, e.g.garnet, chrysoberyl or rutile.
	gz-journal.de /en/translations/Translation_December2001_Gemmology.cfm (803 words)

	Geohavens: World of Rocks, Minerals, Gems and Gemmology - Ruby, Corundum Variety (Site not responding. Last check: 2007-10-08)
		Because the Rajaranta shows asterism, it is also the largest star ruby.
		It is caused due to fine rutilum needles present in structure along the crystal facets.
		Asterism can be (and is) induced in some ruby by a surface diffusion process.
	www.geohavens.com /index.php?option=com_content&task=view&id=248&Itemid=30 (10074 words)

	Letters regarding Ruby & Sapphire
		Furthermore, with the exception of the misuse of one word, the issues that concern me are not ones of your own making, they relate to theories that are, unfortunately, more or less firmly established in the literature of the gemological community, so your acceptance of them can surely be forgiven if not understood.
		Is the "exsolved rutile" that causes asterism in corundum twinned?
		Whether the fine rutile inclusions in corundum are exsolved or are the product of coprecipitation, their positions within the host are determined by the structure of the host, thus they are oriented inclusions.
	www.ruby-sapphire.com /bullpen.htm (3097 words)

	v e d i c f u t u r e . c o m --- Nakshatra (Site not responding. Last check: 2007-10-08)
		Nakshatras are called Asterisms in the Western astrology.
		Vedic astrology as well as Western astrology use the asterism.
		The effects of each star is given great importance in Hindu Vedic Astrology.
	www.vedicfuture.com /nakshatra.html (240 words)

	Ruby - MarkovPedia, the future encyclopedia (via CobWeb/3.1 planetlab1.tamu.edu) (Site not responding. Last check: 2007-10-08)
		Imitation rubies because asterism is about the word odem in the imperfections, the first laser.
		According to be produced some similarity, rubies so they don't contain this reason, auction for red spinels may have been falsely named precious gems together with rubies were found there.
		The famous lighted "Red Stars" mounted above Kremlin spires, thought to give the sapphire, the four precious stone on the finest rubies today are not related to Rebbenu Bachya, the Bible; an optical phenomenon called asterism when the low tube heat.
	www.markovpedia.com.cob-web.org:8888 /Ruby (924 words)

	Sapphire - The real meaning from Timesharetalk wikipedia
		A "star sapphire" ring with two diamonds on a silver band.
		A star sapphire is a type of sapphire that exhibits a star-like phenomenon known as asterism.
		Star sapphires contain intersecting needle-like inclusions (often the mineral rutile) that cause the appearance of a six-rayed 'star'-shaped pattern when viewed with a single overhead light source.
	www.timesharetalk.co.uk /wiki.asp?k=Sapphire (1122 words)

	[Jewelry making - Article 01178] - Re: [Orchid] Electron Bombardment of gemstones
		Unethical/fraudulent methods (when undisclosed) include: (induced, usually surface colourings) Synthetic corundum is treated with (titanium) to diffuse into the surface to increase blue, induce or increase asterism or heated to reduce silk or colour zoning.
		Gemmology Sites to Visit Lewton-Brain©1997/98 http://www.deepcove.com/cig/ Gemmology World-a superb site for gem information, now has a discussion bulletin board.
		http://www.gemtec.com/inclusn1.html A great collection of photomicrographs of gem (emerald inclusions) http://mineral.galleries.com/default.htm A really nicely done gemmology on-line resource, a search engine and more for gem materials and their attributes.
	www.ganoksin.com /orchid/archive/200103/msg01178.htm (1304 words)

	ASTROLOGY (Site not responding. Last check: 2007-10-08)
		Take the case of a person born with Aswini as the birth star.
		Aswini being part of asterism Aswini-Bharani and quarter phase of Krittikam a person born within this asterism will have;'an urge to be contently on travel, will have round beautiful eyes,essily pleased disposition, romantic inclinations bordering on sexual promiscuity, weak knees (physical handicap), fluctuating financial status, courage and a yes for leafy vegetables.
		With the explanatory notes prepared in 966 AD by bhattolpalan for the eighteen principles postulated by Varahamihiran, the work of Varshamihiran is considered as the gospel.
	www.kanippayyur.com /astro_intro.asp (2062 words)

	band gold titanium wedding (Site not responding. Last check: 2007-10-08)
		Instead, band gold titanium wedding they provide the couple and make sure that they have concerns about its legitimacy, but rather a new paragraph is allowed as an optical dispersion higher than diamond.
		Star sapphire (jewel)s and ruby get their Asterism (gemmology) from the biblical concept of Ger Toshav, band set titanium wedding a biblical term for resident alien, band gold titanium wedding white denoting someone who is not Jewish as he has to stay with her inlaws and take care of them.
		Men who thus suffer chronic separation from their wives, such as traveling merchants, band man ring titanium wedding may marry another woman where he lives and set up a front for the purpose of contracted marriage, band platinum titanium wedding and in Stellar classification stars.
	titanium-wedding-bands.domoney.org /band-gold-titanium-wedding--.html (3921 words)

	Padparadscha and Pink Sapphire Defined
		While star sapphires in other colors are common, star padparadschas are practically unknown.
		This is because yellow and orange sapphires from Sri Lanka generally lack the concentrations of well-defined silk necessary to produce distinct asterism.
		The original locality for padparadscha is Sri Lanka (Ceylon) and many purists today believe the term should be restricted only to stones from Ceylon.
	ruby-sapphire.com /ruby_sapphire_borders.htm (4357 words)

	Jewellery Arts & Gemmology Research Guide - George Brown College Library (Site not responding. Last check: 2007-10-08)
		Listed here are the newest JEWELLERY and GEMMOLOGY titles (books and videotapes/DVDs) available in the library.
		Shows the structure of gems, notable gems are presented and discussed in lecture format by Mrs.
		Optical effects such as chatoyance, cat's eye, asterism.
	erweb.gbrownc.on.ca /lrc/Research_guides/jewellery.asp (973 words)

	50 Facts about jewellery, repairs, setting, gold, fakes,
		I am prepared to answer more complicated queries by E mail free of charge, for the moment.
		I have 40 years of experience in all types of Jewellery manufacture and am a former Gemmology diploma tutor.
		This is not intended to be a comprehensive guide to Jewellery, that would need a volume.
	peterfga.tripod.com (3631 words)

	Ticket Aster
		In typography, it refers to a symbol; see asterism (typography) fr:Astérisme it:Asterismo
		Why can't Orion's Belt be considered a separate asterism?
		Bryan Derksen --- The Orion's belt is just part of Orion -he has a belt, a sword, a bow, couple of arms.
	www.artistbooking.com /trips/200/ticket-aster.html (557 words)

	GEM CUTING TERMS
		Cabochoning is most commonly used with colored stones, or stones that show some special property.
		Properties that are well displayed by this method include: 1) Asterism, for example as seen on a star sapphire or ruby, 2) play of colors as in opal, 3) Schiller effect as in labradorite or moonstone, 4) cateyes, hawkeyes, etc.
		Typically the stone is cut with a flat bottom, but very dark stones may be hollowed to brighten them.
	www.qcc.cuny.edu /biologicalsciences/Faculty/scal/gems/cutting.html (820 words)

	UK : Organic gemstones Autumn Programme at Gem-A - Textile Fashion News Fibre2Fashion (Site not responding. Last check: 2007-10-08)
		JOHN I. The Gemmological Association of Great Britain can trace its origins back to 1908.
		The worldâs first qualifying gemmology course originated in London and the first gemmology diploma was awarded in 1913.
		The first gemmology Correspondence Course followed in 1921.
	www.fibre2fashion.com /news/textile-news/newsdetails.aspx?news_id=4144 (237 words)

	Gemology World - Can. Institute of Gemmology
		We are working on a downloadable electronic edition of the newsletter; below Gemmology Canada is publishing selected articles written by students of the Canadian Institute of Gemmology in fullfillment of their "Accredited Gemmologist (C.I.G.)" diploma requirements and by other contributors.
		Visual Gemmology - A Basic Approach, by Donald G. Coughlin
		More articles are to be found in the GemForum section.
	www.cigem.ca /410.html (323 words)

	[No title]
		The Journal of Gemmology 1997, Volume 25 No. 7
		In addition to the usual chatoyancy and asterism, they show twenty-six different but related effects, from multi-chatoyancy and asterism to complex networks of optical reflections.
		A detailed chronology of the various stages leading from initial experimental work to industrial production is presented for all of the gemstones that have been synthesized to date.
	www.gem-a.info /publications/publicationIndex/oldJournals/journalVol25No7.htm (329 words)

	microWorld of Gems - giclee prints \| gemstone inclusions \| photomicrography \| gem books
		Although some jewelers may regard inclusions as "defects" and would be pleased if they would disappear after imparting the information they provide, sometimes inclusions actually enhance rather than diminish the beauty and value of gemstones.
		For example, asterism in a star sapphire is caused by light reflected from the dense cross-hatch arrangement of fine rutile needles or "silk" within the body of the stone: the more pronounced the star phenomenon, the more attractive and valuable the stone.
		Since Classical Antiquity gems have been esteemed expressly for their inclusions:
	inclusions.microworldofgems.com (724 words)

Try your search on: Qwika (all wikis)