Guilding the Stone: October Trivia Quiz

Answer: Common Opal

Before the invention of the electron microscope it was not possible to discover how the structure of common and precious opals differed, as the degree of magnification required was beyond the limits of the optical microscope. Once it was possible to examine the opal's structure it was discovered that it was made up of small spheres of silica surrounding a central nucleus. The difference between common and precious stones was that common opals had an irregular structure with spheres of varying sizes, whereas the precious opals had regular stacks of similar sized spheres.

The "play of colour" refers to the display of colour that can be seen inside an opal. This colour is produced by the diffraction of light as it travels through the silica and the areas between the spheres and the refraction of light from the surface of the gem. The colour that is displayed can change with the angle that the stone is viewed at.

The irregularity in the common opals, combined with some smaller sized silica spheres, means that the light cannot be diffracted in the way that it is in precious opals. The colour displayed by precious opals is partially dependent on the size of the spheres it contains. The smallest spheres produce a violet colour, the largest produce red.

Black opals are the most valuable of precious opals as the darker background of the stone makes the play of colour stand out more. Crystal opals are precious opals with a lighter background. A boulder opal is precious opal set in firestone.

Answer: Elizabeth II of the United Kingdom

The opal was found in Andamooka following a deliberate attempt to find the finest opal in Australia, in anticipation of Queen Elizabeth's visit. The necklace it was set in was made of 18-carat palladium and was inset with diamonds. It was presented to Elizabeth II at a banquet in Adelaide, which was named after Adelaide of Saxe-Meiningen, the wife of King William IV of the United Kingdom.

Answer: Halley's Comet Opal

The opal was discovered by a group of miners who called themselves "The Lunatic Hill Syndicate" at about the time that Halley's Comet made its first appearance in Australian skies for 76 years. It measures 100 x 66 x 63 mm and has a band of green and orange running through it.

There is a giant opal called the "Olympic Australis" which was discovered in 1956 and was named in celebration of the Melbourne Olympics, the first Games to be held in the southern hemisphere.

Live Aid took place in 1985. Black Monday was in 1987.

Answer: Sir Walter Scott

"Anne of Geierstein" also known as "The Maiden of the Mist" was the last of Scott's "Waverley" novels and the most commercially successful of his later works. Each of the Waverley novels was published anonymously as "The Author of Waverley" even though, in 1827, Scott had publicly acknowledged his own authorship of the books.

Set in the time of the Wars of the Roses, the novel follows two exiled Lancastrians, the Earl of Oxford and his son, as they travel through Switzerland to attempt to convince Charles the Bold, the Duke of Burgundy, to support the Lancastrian cause. In the course of their travels, the two men are caught in a storm and seek refuge in the home of the Count of Geierstein, where they meet, and the son falls in love with, the Count's beautiful daughter, Anne.

The Baroness of Arnheim, the wife of the Count, had a beautiful opal with "a slight tinge of red like a spark of fire." When the opal, which acts as a talisman for the Baroness, is dripped on with holy water, it turns transparent and she instantly drops to the ground in pain. She is taken to her chamber to recover. When she is visited two hours later, "no traces of her could be discovered, unless that there was about a handful of light gray ashes, found on the bed where she had been laid."

Answer: Australia

The main opal fields in Australia are found in South Australia and New South Wales. Each of the mined areas has a different type of opal with Lightning Ridge in NSW and Minibie in South Australia producing almost all of the world's high-value black opal.

The Australian women's basketball team claimed their first world title in 2006 with a victory over Russia in the final. They had finished third in the previous two tournaments. They also claimed the silver medal in the 2000, 2004 and 2008 Olympic tournaments.

Answer: Mars

The opal is formed by crystals of hydrated silica, and the water content of the gem can range from anywhere between three and twenty per cent of the total mass.

Though opals had been found in one crater on Mars' surface prior to 2008, the widespread presence of the mineral in other surface areas has changed the prevailing view of when Mars ceased to have water on its surface. By measuring the pH value of clays and other hydrated minerals in Mars terrain, it had been estimated that Mars became free of surface water sometime around three billion years ago (the scarcer the water on the surface, the more acidic it becomes). However, the opal that was discovered dates to less than 2.5 billion years ago.

The discovery suggests that future explorations of the planet's surface that are looking for signs of life, might find their best evidence at the site of the opal fields.

Answer: Starburst

Opal Fruits are best remembered in the UK for the tagline "Made to make your mouth water". The original flavours of the sweets have been modified on several occasions. Firstly, the lemon and lime flavours were dropped in favour of a blackcurrant and a lemon & lime variety. Later, more brands were added to the Starburst stable; Starburst Sour Chews, Starburst Smoothies and Starburst Choozers, which introduced the flavours of blueberry, banana, passion fruit and mango.

Answer: Starman

Ted Knight was a genius scientist who developed the cosmic rod, a device that could create cosmic energy from starlight. Using this device he made himself into Starman and joined the Justice Squad of America in 1941. Coincidentally, this is also when he made his first appearance in DC's "Adventure Comics". In the 1990s, he retired and passed the Starman mantle on to his son, David, and following David's death, to his second son, Jack. By this time, he had earned his own comic book series, "Starman".

Their home city, Opal City, started out life as the Port O'Souls on the coast of Chesapeake Bay in northern Maryland. It was renamed as Opal City in the mid-19th century and underwent a re-building program in the early years of the 20th century. As a consequence, many of its buildings are in the Art Deco style. Ted Knight saved it from destruction when he uprooted the post office and sent it into space after a nuclear bomb was discovered buried within it.

Other superheroes who live in Opal City include Phantom Lady, Black Condor and the Elongated Man.

Answer: Butterfly

The Lycaenidae family of butterflies is myrmecophilous, which means that the butterflies live in association with ants, both mutually and parasitically. Some opal butterfly caterpillars produce nectar for the ants to feed on and also produce chemicals that mimic ant pheromones so that the ants will defend them against attack. Also, the ants' eggs and pupae and sometimes their regurgitations can provide food for the caterpillar. Lycaenid pupae often have thicker skin than average to protect against ant bites.

Many of the species of opals are classified as endangered or critically endangered by the International Union for Conservation of Nature.

Answer: Operating Process Application Library

OPAL (Oracle/PHP/Apache/Linux) is a software solution stack comprising an operating system (Linux), server software (Apache), a programming language (Pre-hypertext Programming or PHP) and database software (Oracle). It is an alternative software solution to the more common LAMP stack, which replaces Oracle with MySQL.

The OPAL project (OPtimized Applicative Language) is an open source, algebraic programming language developed at the Technische Universität Berlin.

OPAL software (Open Physics Abstraction Layer) is software that simulates the action of virtual objects in a real life framework. For example, if a spherical object were dropped onto a sloped surface with several obstacles upon it, the software would predict where the object would come to rest. OPAL software is often used in video game development.