There is one test based on " Brazil law twinning " ( a form of quartz twinning where right and left hand quartz structures are combined in a single crystal ) which can be used to identify synthetic amethyst rather easily.

Crystal twinning is common in feldspars, especially polysynthetic twins in plagioclase and Carlsbad twins in alkali feldspars.

Feldspar within a pegmatite may display exaggerated and perfect twinning, exsolution lamellae, and when affected by hydrous crystallization, macroscale graphic texture is known, with feldspar and quartz intergrown.

Until this point in development, twinning is possible.

There is no known genetic link for identical twinning.

Studies show that there is a genetic basis for dizygotic twinning.

This is in marked contrast to dizygotic twinning, which ranges from about six per thousand births in Japan ( almost similar to the rate of identical twins, which is around 4 – 5 ) to 15 and more per thousand in some parts of India and up to over 20 in some Central African countries.

Although examples of half-identical twins have been found, the exact mechanism of their conception is not well-understood, but could theoretically occur in polar body twinning where sperm cells fertilize both the ovum and the second polar body.

This situation is not the same as the common form of fraternal twinning, in which two genetically different ova are fertilized by two genetically different sperm.

There is a twinning between Kreis Dithmarschen and Restormel Borough Council.

Lambeth also has twinning arrangements with Bluefields in Nicaragua ; Moskvoretsky in Russia ( although this is abeyance since changes to the city government of Moscow ); Brooklyn, New York in the United States ; Shinjuku in Japan ; and Spanish Town in Jamaica.

In the City Hall of Nevada City there is a room dedicated to the twinning and houses Cornish memorabilia and items donated on various exchanges.

* The choice of twinning with both an Israeli city and a Palestinian one is Opsterland's modest contribution to trying to solve the Israeli-Palestinian Conflict.

Meerssen is a founding member of the Douzelage, a unique town twinning association of 24 towns across the European Union.

Oxelösund is a member of the Douzelage, a unique town twinning association of 24 towns across the European Union.

The structure is named in recognition of the twinning ties between Norwich and Novi Sad in Serbia.

Brighouse is twinned with Lüdenscheid in Germany, the link beginning with an exchange by Brighouse Children's Theatre in 1950 followed by a civic twinning charter in 1960.

Houffalize is a founding member of the Douzelage, a unique town twinning association of 24 towns across the European Union.

Judenburg is a member of the Douzelage, a unique town twinning association of 24 towns across the European Union.

Jarrow is twinned with the following towns, under the umbrella of the South Tyneside town-twinning project which saw individual twinning projects brought together in 1974:

The Japanese Shogun made him a samurai ( warrior ), he is significant to Medway because this has led to the twinning with Yokosuka and Ito.

Plasticity in a crystal of pure metal is primarily caused by two modes of deformation in the crystal lattice, slip and twinning.

Half-identical or semi-identical twins ( also referred to as " half twins ") are the result of a very rare form of twinning in which the twins inherit exactly the same genes from their mother but different genes from their father.

The authors were unable to predict whether a healthy fetus could result from a polar body twinning.

The twinning of the two words result in the coining of " Amanpulo " or " peace island " in reference to the tranquil island of Pamalican.

Deformation twinning is a common result of regional metamorphism.

Factors influencing a crystal's habit include: a combination of two or more crystal forms ; trace impurities present during growth ; crystal twinning and growth conditions ( i. e., heat, pressure, space ); and specific growth tendencies like growth striations.

The most recent twinning visit took place in Moyeuvre during May 2010.

A twinning project with the Bangladesh Scouts, known as the " Bangladesh-Australia Child Health " ( BACH ) project made a dramatic impact on child health in project villages during its operation from 1986 to 1992.

This old College was an English hospital during the first world war and a twinning is still active in 2008 with Queen Elizabeth's Grammar School, Faversham ( Kent ).

Fivefold twinning in a gold nanoparticle ( Transmission electron microscope | electron microscope image ).

A number of cities around the world ( especially those which had suffered similar wartime devastation ) established sister / friendship / twinning links ( see list below ) in the spirit of solidarity or reconciliation.

Crystals can be marred by twinning, which can occur when a unit cell can pack equally favorably in multiple orientations ; although recent advances in computational methods may allow solving the structure of some twinned crystals.

Other important investments that have helped position Sydney as an eastern hub of Nova Scotia include the twinning of Highway 125 and the creation of the Centre for Sustainability in the Environment at nearby Cape Breton University, which draws hundreds of international students each year.

The Yoruba have the highest rate of twinning in the world, at 45-50 twin sets ( or 90-100 twins ) per 1, 000 live births, possibly because of high consumption of a specific type of yam containing a natural phytoestrogen which may stimulate the ovaries to release an egg from each side.

Each summer an average of four 4th / 5th year students partake in the Phoenix Youth Ambassador Program, which is facilitated by the city of Phoenix twinning committee and the Ennis Chamber Of Commerce.

In 2001 Märkischer Kreis entered a twinning arrangement with Racibórz ( Ratibor ), a county in Poland, which was formerly part of Silesia, Germany.

This is a list of " twin towns " or " sister cities " — that is, pairs of towns or cities in different countries which have town twinning arrangements.

In 2001, the Association of Baptist Churches established a " twinning " agreement with the Baptist Union of Great Britain, which is promoted by the organizations as " a means to support each other in prayer, developing ministry, mutual benefit from the experience of the other, fellowship and encouragement.

A twinning website exists, the link of which can be seen at the bottom of the page under ' External links '.

" He added: " This twinning will contribute to the process of improving and developing the performance of the municipality of Miniara, especially after the discounts, which affected the municipalities of Akkar, including Mayor Miniara, which impacted negatively on municipal work ," indicating that this is the first municipality in the Akkar region, which completed twinning with a foreign municipality, thanks to expatriates in Colombia of Lebanese origin of the Akkar region.

Vancouver, British Columbia, was also a notable city to enter into an intercontinental twinning arrangement when, in 1944, it twinned with the Ukrainian city of Odessa, which at the time was part of the Soviet Union.

Plouézec is twinned with the Irish town of Ballinamore and the twinning committee hosts a famous Fest Noz festival every August around the Moulin de Craca which regularly draws thousands of visitors.