"Nature's Fireworks" - A Beginner's Guide to OPAL - Part 5 Types of Opal

Written by Stuart Bazga

Duringrepparttar Cretaceous period (65-140 million years ago) deserts were an inland sea teeming with life. The sea gradually receded layingrepparttar 146821 foundation of silica that would formrepparttar 146822 opal of today. Duringrepparttar 146823 mid-tertiary period, changes inrepparttar 146824 earth’s climate caused quantities of soluble silica to be released fromrepparttar 146825 sediment, finding its way down through cracks and faults, eventually hardening over time. This hardening continued to form common and precious opal.

The vivid array of colour inrepparttar 146826 opal is fromrepparttar 146827 uniform alignment ofrepparttar 146828 silica particles. The size ofrepparttar 146829 particles determinesrepparttar 146830 colour as light refracts through it.

Unlike many other gemstones, opal doesn’t occur in lengthy veins or concentrations. Instead, small clusters may be spread over a vast area and divided into precious or gem quality and common. Opal is found in many varieties, but precious opal represents only a small percentage ofrepparttar 146831 total mined.

Black Opal:

Black opal isrepparttar 146832 rarest and most valuable of all opals and is generally found as a bar of various colours in a dark body. In addition, there is also Semi black and black Crystal.

Black opals from Lightning Ridge, Mintabie and Andamooka in Australia account for 99.9% of all opals inrepparttar 146833 world.

Boulder Opal:

Boulder opal, found inrepparttar 146834 fields of Queensland, is classified as a solid opal and occurs as thin veins of precious opal in cracks and cavities of ironstone. During processing,repparttar 146835 stone is cut leavingrepparttar 146836 natural host rock as backing. The opal occurs as either a solid piece of colour on top ofrepparttar 146837 ironstone or showing as flashing flecks of colour throughoutrepparttar 146838 stone.

Light Opal (White or Milky):

Light opal can be found in Coober Pedy, Andamooka and Mintabie in South Australia. A full range of colours can be found, withrepparttar 146839 background colour either white or light blue.

Crystal Opal:

Asrepparttar 146840 name suggests, crystal opal has a brilliant, crystal appearance, with a translucent or transparent background. When viewed on a dark surfacerepparttar 146841 colours spring to life.

Picture Opals:

Picture opals are so called because their pattern forms an image of an object or person. A good imagination is sometimes required to visualiserepparttar 146842 object/person.

Fire Opal:

The term “Fire opal” is commonly used to describerepparttar 146843 clear orange crystal opal that comes from Mexico, some of which have a play of colour, although many have just an orange or reddish base with no play of colour.

Opalised Fossils:

Buried inrepparttar 146844 layers where opal mining occurs arerepparttar 146845 remains of a world over a hundred million years old, brought torepparttar 146846 surface by miners searching for gemstones. These fossils includerepparttar 146847 remains of dinosaurs, shells, mammals, plants and fish. Some of these fossils have been opalised, a process in which silica-laden waters have gradually replacedrepparttar 146848 organic material.

Common Opal:

Common opal is classified as non-gem quality opal, mostly opaque and showing no play of colour.

Matrix Opal:

A short biography on some of Europe's most loved and hated Monarchs - Pt 1 Vlad Tepes (Dracula)

Written by Stuart Bazga

Vlad Tepes or Dracula was born in 1431, inrepparttar fortress of Sighisoara, Romania. His father wasrepparttar 146689 military governor of Transylvania and a member ofrepparttar 146690 Order ofrepparttar 146691 Dragon. The order was created in 1387 byrepparttar 146692 Holy Roman Emperor and his second wife, Barbara Cilli.

Inrepparttar 146693 winter of 1436-1437, Vlad(Dracul) became prince of Wallachia and took up residence atrepparttar 146694 palace of Tirgoviste,repparttar 146695 princely capital. In 1442, he and his younger brother Radu were taken hostage byrepparttar 146696 Turkish Sultan Murad II. Dracul was held in Turkey until 1448, while his brother Radu decided to stay there until 1462.

At 17 years old, Vlad, supported by troops lent to him by pasha Mustafa Hassan, tried to seizerepparttar 146697 Wallachian throne but was defeated by Vladislav II (who had earlier assassinated his father and oldest brother ) after two months or armed conflict. Vlad had to wait until 1456, when he was able to seek retribution against his father's assassin.

Vlad's first act of vengeance was aimed atrepparttar 146698 boyars of Tirgoviste forrepparttar 146699 killing of his father and older brother Mircea. Around Easter of 1459, Vlad had allrepparttar 146700 boyar families arrested and impaledrepparttar 146701 elder members on stakes while forcingrepparttar 146702 others to march fromrepparttar 146703 capital torepparttar 146704 town of Poenari. He then ordered them to build him a fortress onrepparttar 146705 ruins of an older outpost overlookingrepparttar 146706 Arges River. Many nobles died inrepparttar 146707 construction of this castle,repparttar 146708 ruins of which can still be seen today.

Vlad became known for his brutal punishment techniques; often ordering people to be skinned, decapitated, blinded, roasted, hacked, buried alive, stabbed and blinded to name a few. He also liked to cut off his victim noses, ears and sexual organs. But his favourite form of torture was impalement on stakes, hencerepparttar 146709 surname "Tepes" which means "The Impaler" inrepparttar 146710 Romanian language. It was this form of punishment that he used against Transylvanian merchants who ignored his trade laws.

There are many tales aboutrepparttar 146711 psyche of Vlad Tepes. He was known throughoutrepparttar 146712 country for his fierce adherence to honesty and order. Almost any crime, from lying and stealing to killing, could be punished by impalement. Being so confident inrepparttar 146713 efficiency of his law, Dracula placed a golden cup on display inrepparttar 146714 central square of Tirgoviste. The cup could be used by thirsty travellers, but had to remain onrepparttar 146715 square. It was never stolen and remained entirely untouched throughout Vlad's reign. He looked uponrepparttar 146716 poor, vagrants and beggars as thieves. Consequently, he invited allrepparttar 146717 poor and sick of Wallachia to his court in Tirgoviste for a magnificent feast. After his guests had eaten and drunk their fill, Dracula orderedrepparttar 146718 hall boarded up and set on fire. There were no survivors.

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