0_Wizard
One of my favorite colors is blue. It lies between violet and green on the light spectrum.
It lies between violet and green on the spectrum of visible light.
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Blue
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Grow light
A grow light or plant light is an artificial light source, generally an electric light, designed to stimulate plant growth by emitting a light appropriate for photosynthesis. Grow lights are used in applications where there is either no naturally occurring light, or where supplemental light is required. For example, in the winter months when the available hours of daylight may be insufficient for the desired plant growth, lights are used to extend the time the plants receive light. If plants do not receive enough light, they will grow long and spindly. Grow lights either attempt to provide a light spectrum similar to that of the sun, or to provide a spectrum that is more tailored to the needs of the plants being cultivated.
Light-emitting diode
A light-emitting diode (LED) is a two-lead semiconductor light source. It is a p–n junction diode that emits light when activated. When a suitable voltage is applied to the leads, electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called electroluminescence, and the color of the light (corresponding to the energy of the photon) is determined by the energy band gap of the semiconductor. LEDs are typically small (less than 1 mm) and integrated optical components may be used to shape the radiation pattern. Appearing as practical electronic components in 1962, the earliest LEDs emitted low-intensity infrared light.
Theory of Colours
Theory of Colours (German: "Zur Farbenlehre") is a book by Johann Wolfgang von Goethe about the poet's views on the nature of colours and how these are perceived by humans. It was published in German in 1810 and in English in 1840. The books contains detailed descriptions of phenomena such as coloured shadows, refraction, and chromatic aberration. The work originated in Goethe's occupation with painting and mainly exerted an influence on the arts (Philipp Otto Runge, J. M. W. Turner, the Pre-Raphaelites, Wassily Kandinsky). The book is a successor to two short essays entitled "Contributions to Optics".
Fluorescence
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore lower energy, than the absorbed radiation. The most striking example of fluorescence occurs when the absorbed radiation is in the ultraviolet region of the spectrum, and thus invisible to the human eye, while the emitted light is in the visible region, which gives the fluorescent substance a distinct color that can only be seen when exposed to UV light. Fluorescent materials cease to glow immediately when the radiation source stops, unlike phosphorescence, where they continue to emit light for some time after.
Color vision
Color vision is the ability of an organism or machine to distinguish objects based on the wavelengths (or frequencies) of the light they reflect, emit, or transmit. Colors can be measured and quantified in various ways; indeed, a person's perception of colors is a subjective process whereby the brain responds to the stimuli that are produced when incoming light reacts with the several types of cone cells in the eye. In essence, different people see the same illuminated object or light source in different ways. Isaac Newton discovered that white light, after being split into its component colours when passed through a dispersive prism, could, by passing them through a different prism, be recombined to make white light.
Purple
Purple is a color intermediate between blue and red. It is similar to violet, but unlike violet, which is a spectral color with its own wavelength on the visible spectrum of light, purple is a composite color made by combining red and blue. According to surveys in Europe and the U.S., purple is the color most often associated with royalty, magic, mystery and piety. When combined with pink, it is associated with eroticism, femininity and seduction. Purple was the color worn by Roman magistrates; it became the imperial color worn by the rulers of the Byzantine Empire and the Holy Roman Empire, and later by Roman Catholic bishops.
On Vision and Colors
On Vision and Colors () is a treatise by Arthur Schopenhauer that was published in May 1816 when the author was 28 years old. Schopenhauer had extensive discussions with Johann Wolfgang von Goethe about the poet's "Theory of Colours" of 1810, in the months around the turn of the years 1813 and 1814, and basically shared Goethe's views. Schopenhauer tried to demonstrate physiologically that color is "specially modified activity of the retina." The initial basis for Schopenhauer's color theory comes from Goethe's chapter on physiological colors, which discusses three principal pairs of contrasting colors: red/green, orange/blue, and yellow/violet.
1_Apprentice
I love blue!!! I wonder where the pigment comes from in the earth?
0_Wizard
It comes from many sources. The semi-precious stone lapis lazuli was used in both Ancient Egypt and later on in The Renaissance to make various pigments.
The semi-precious stone lapis lazuli was used in ancient Egypt for jewellery and ornament and later, in The Renaissance, to make the pigment ultramarine, the most expensive of all pigments.
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Blue
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Lapis lazuli
Lapis lazuli (, ), or lapis for short, is a deep blue metamorphic rock used as a semi-precious stone that has been prized since antiquity for its intense color. As early as the 7th millennium BC, lapis lazuli was mined in the Sar-i Sang mines, in Shortugai, and in other mines in Badakhshan province in northeast Afghanistan. Lapis was highly valued by the Indus Valley Civilisation (3300–1900 BC). Lapis beads have been found at Neolithic burials in Mehrgarh, the Caucasus, and even as far from Afghanistan as Mauritania. It was used in the funeral mask of Tutankhamun (1341–1323 BC). At the end of the Middle Ages, lapis lazuli began to be exported to Europe, where it was ground into powder and made into ultramarine, the finest and most expensive of all blue pigments.
Blue
Blue is one of the three primary colours of pigments in painting and traditional colour theory, as well as in the RGB colour model. It lies between violet and green on the spectrum of visible light. The eye perceives blue when observing light with a dominant wavelength between approximately 450 and 495 nanometres. Most blues contain a slight mixture of other colors; azure contains some green, while ultramarine contains some violet. The clear daytime sky and the deep sea appear blue because of an optical effect known as Rayleigh scattering. An optical effect called Tyndall scattering explains blue eyes.
Pigment
A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light. Many materials selectively absorb certain wavelengths of light. Materials that humans have chosen and developed for use as pigments usually have special properties that make them ideal for coloring other materials. A pigment must have a high tinting strength relative to the materials it colors. It must be stable in solid form at ambient temperatures.
Ancient Egypt
Ancient Egypt was a civilization of ancient Northeastern Africa, concentrated along the lower reaches of the Nile River in the place that is now the country Egypt. It is one of six historic civilizations to arise independently. Egyptian civilization followed prehistoric Egypt and coalesced around 3100 BC (according to conventional Egyptian chronology) with the political unification of Upper and Lower Egypt under Menes (often identified with Narmer). The history of ancient Egypt occurred as a series of stable kingdoms, separated by periods of relative instability known as Intermediate Periods: the Old Kingdom of the Early Bronze Age, the Middle Kingdom of the Middle Bronze Age and the New Kingdom of the Late Bronze Age.
Egyptian faience
Egyptian faience is a sintered-quartz ceramic displaying surface vitrification which creates a bright lustre of various colours, with blue-green being the most common. Defined as a “material made from powdered quartz covered with a true vitreous coating, usually in a transparent blue or green isotropic glass," faience is distinct from the crystalline compound Egyptian blue. Notably, faience is considerably more porous than glass proper and can be cast in molds to create vessels or objects. Although not properly pottery, as (until late periods) it contains no clay and instead contains the major elemental components of glass (silica), faience is frequently discussed in surveys of ancient pottery, as in stylistic and art-historical terms objects made in it are closer to pottery styles than ancient Egyptian glass.
Imports to Ur
Imports to Ur reflect the cultural and trade connections of the Sumerian city of Ur. During the period of the Early Dynastic III royal cemetery (ca. 2600 BC), Ur was importing elite goods from geographically distant places. These objects include precious metals such as gold and silver, and semi-precious stones, namely lapis lazuli and carnelian. These objects are all the more impressive considering the distance from which they traveled to reach Mesopotamia and Ur specifically. Mesopotamia is very well suited to agricultural production for both plants and animals but is lacking in metals, minerals and stones.
List of Deltora Quest characters
The "Deltora" series features a wide line of characters, both important and minor. The series also features many different monsters and creatures that appeared in all of the many different books. This article is a list of the many different characters and creatures that have appeared in the Deltora series. Lief was raised as a blacksmith's son in the run-down city of Del after the invasion. Hot-headed and impatient at the start of the series, all he wanted to do was go out and explore the city. On the night of his sixteenth birthday, he leaves on his father's quest to restore the Belt of Deltora, the only thing that can save their land and the heir from the tyranny of the Shadow Lord.
1_Apprentice
That's interesting. What kind of art media was it first made into?
0_Wizard
The Ancient Egyptians used it for jewellery and ornaments and during the Renaissance it was used to make the pigment ultramarine, a very expensive pigment.
The semi-precious stone lapis lazuli was used in ancient Egypt for jewellery and ornament and later, in The Renaissance, to make the pigment ultramarine, the most expensive of all pigments.
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Blue
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Blue
Blue is one of the three primary colours of pigments in painting and traditional colour theory, as well as in the RGB colour model. It lies between violet and green on the spectrum of visible light. The eye perceives blue when observing light with a dominant wavelength between approximately 450 and 495 nanometres. Most blues contain a slight mixture of other colors; azure contains some green, while ultramarine contains some violet. The clear daytime sky and the deep sea appear blue because of an optical effect known as Rayleigh scattering. An optical effect called Tyndall scattering explains blue eyes.
Ultramarine
Ultramarine is a deep blue color and a pigment which was originally made by grinding lapis lazuli into a powder. The name comes from the Latin "ultramarinus", literally "beyond the sea", because the pigment was imported into Europe from mines in Afghanistan by Italian traders during the 14th and 15th centuries. Ultramarine was the finest and most expensive blue used by Renaissance painters. It was often used for the robes of the Virgin Mary, and symbolized holiness and humility. It remained an extremely expensive pigment until a synthetic ultramarine was invented in 1826. The pigment consists primarily of a zeolite-based mineral containing small amounts of polysulfides.
Ancient Egypt
Ancient Egypt was a civilization of ancient Northeastern Africa, concentrated along the lower reaches of the Nile River in the place that is now the country Egypt. It is one of six historic civilizations to arise independently. Egyptian civilization followed prehistoric Egypt and coalesced around 3100 BC (according to conventional Egyptian chronology) with the political unification of Upper and Lower Egypt under Menes (often identified with Narmer). The history of ancient Egypt occurred as a series of stable kingdoms, separated by periods of relative instability known as Intermediate Periods: the Old Kingdom of the Early Bronze Age, the Middle Kingdom of the Middle Bronze Age and the New Kingdom of the Late Bronze Age.
Red
Red is the colour at the end of the visible spectrum of light, next to orange and opposite violet. It has a dominant wavelength of approximately 625–740 nanometres. It is a primary color in the RGB color model and the CMYK color model, and is the complementary color of cyan. Reds range from the brilliant yellow-tinged scarlet and vermillion to bluish-red crimson, and vary in shade from the pale red pink to the dark red burgundy. The red sky at sunset results from Rayleigh scattering, while the red color of the Grand Canyon and other geological features is caused by hematite or red ochre, both forms of iron oxide.
Lapis lazuli
Lapis lazuli (, ), or lapis for short, is a deep blue metamorphic rock used as a semi-precious stone that has been prized since antiquity for its intense color. As early as the 7th millennium BC, lapis lazuli was mined in the Sar-i Sang mines, in Shortugai, and in other mines in Badakhshan province in northeast Afghanistan. Lapis was highly valued by the Indus Valley Civilisation (3300–1900 BC). Lapis beads have been found at Neolithic burials in Mehrgarh, the Caucasus, and even as far from Afghanistan as Mauritania. It was used in the funeral mask of Tutankhamun (1341–1323 BC). At the end of the Middle Ages, lapis lazuli began to be exported to Europe, where it was ground into powder and made into ultramarine, the finest and most expensive of all blue pigments.
Clothing in the ancient world
The preservation of fabric fibers and leathers allows for insights into the attire of ancient societies. The clothing used in the ancient world reflects the technologies that these peoples mastered. In many cultures, clothing indicated the social status of various members of society. The development of attire and fashion is an exclusively human characteristic and is a feature of most human societies. Clothing made of materials such as animal skins and vegetation was initially used by early humans to protect their bodies from the elements. The usage of clothing and textiles across the ages reflects the varying development of civilizations and technologies.
Jewellery
Jewellery (British English) or jewelry (American English) consists of small decorative items worn for personal adornment, such as brooches, rings, necklaces, earrings, pendants and bracelets. Jewellery may be attached to the body or the clothes, and the term is restricted to durable ornaments, excluding flowers for example. For many centuries metal, often combined with gemstones, has been the normal material for jewellery, but other materials such as shells and other plant materials may be used. It is one of the oldest type of archaeological artefact – with 100,000-year-old beads made from "Nassarius" shells thought to be the oldest known jewellery.
1_Apprentice
Oh wow so much uses! So how old is the color blue exactly?
0_Wizard
Well, Egyptian civilization followed prehistoric Egypt and came together around 3100 BC.
Egyptian civilization followed prehistoric Egypt and coalesced around 3100 BC (according to conventional Egyptian chronology) with the political unification of Upper and Lower Egypt under Menes (often identified with Narmer).
self_Ancient_Egypt_2
Ancient Egypt
self_2_Ancient_Egypt
Ancient Egypt
Ancient Egypt was a civilization of ancient Northeastern Africa, concentrated along the lower reaches of the Nile River in the place that is now the country Egypt. It is one of six historic civilizations to arise independently. Egyptian civilization followed prehistoric Egypt and coalesced around 3100 BC (according to conventional Egyptian chronology) with the political unification of Upper and Lower Egypt under Menes (often identified with Narmer). The history of ancient Egypt occurred as a series of stable kingdoms, separated by periods of relative instability known as Intermediate Periods: the Old Kingdom of the Early Bronze Age, the Middle Kingdom of the Middle Bronze Age and the New Kingdom of the Late Bronze Age.
Ancient Egyptian deities
Ancient Egyptian deities are the goddesses and gods worshipped in ancient Egypt. The beliefs and rituals surrounding these deities formed the core of ancient Egyptian religion, which emerged sometime in prehistory. Deities represented natural forces and phenomena, and the Egyptians supported and appeased them through offerings and rituals so that these forces would continue to function according to "maat", or divine order. After the founding of the Egyptian state around 3100 BC, the authority to perform these tasks was controlled by the pharaoh, who claimed to be the representative of the deities and managed the temples where the rituals were carried out.
History of writing
The history of writing traces the development of expressing language by letters or other marks and also the studies and descriptions of these developments. In the history of how systems of representation of language through graphic means have evolved in different human civilizations, more complete writing systems were preceded by "proto-writing", systems of ideographic or early mnemonic symbols. "True writing", in which the content of a linguistic utterance is encoded so that another reader can reconstruct, with a fair degree of accuracy, the exact utterance written down, is a later development.
Egyptian mythology
Egyptian mythology is the collection of myths from ancient Egypt, which describe the actions of the Egyptian gods as a means of understanding the world. The beliefs that these myths express are an important part of ancient Egyptian religion. Myths appear frequently in Egyptian writings and art, particularly in short stories and in religious material such as hymns, ritual texts, funerary texts, and temple decoration. These sources rarely contain a complete account of a myth and often describe only brief fragments. Inspired by the cycles of nature, the Egyptians saw time in the present as a series of recurring patterns, whereas the earliest periods of time were linear.
Prehistoric Egypt
The prehistory of Egypt spans the period from earliest human settlement to the beginning of the Early Dynastic Period of Egypt around 3100 BC, starting with the first Pharaoh, Narmer for some egyptologists, Hor-Aha for others, (also known as Menes). This Predynastic era is traditionally equivalent to the final part of the Neolithic period beginning c. 6000 BC, and corresponds to the Naqada III period. The dates of the Predynastic period were first defined before widespread archaeological excavation of Egypt took place, and recent finds indicating very gradual Predynastic development have led to controversy over when exactly the Predynastic period ended.
Ancient history
Ancient history is the aggregate of past events from the beginning of recorded human history and extending as far as the Early Middle Ages or the Postclassical Era. The span of recorded history is roughly 5,000 years, beginning with Sumerian Cuneiform script, the oldest discovered form of coherent writing from the protoliterate period around the 30th century BC. The term classical antiquity is often used to refer to history in the Old World from the beginning of recorded Greek history in 776 BC (First Olympiad). This roughly coincides with the traditional date of the founding of Rome in 753 BC, the beginning of the history of ancient Rome, and the beginning of the Archaic period in Ancient Greece.
Ancient Egyptian literature
Ancient Egyptian literature was written in the Egyptian language from ancient Egypt's pharaonic period until the end of Roman domination. It represents the oldest corpus of Egyptian literature. Along with Sumerian literature, it is considered the world's earliest literature. Writing in ancient Egypt—both hieroglyphic and hieratic—first appeared in the late 4th millennium BC during the late phase of predynastic Egypt. By the Old Kingdom (26th century BC to 22nd century BC), literary works included funerary texts, epistles and letters, hymns and poems, and commemorative autobiographical texts recounting the careers of prominent administrative officials.
1_Apprentice
Was it the first pigment to be discovered or were others before blue?