{"id":4582,"date":"2026-02-03T23:12:19","date_gmt":"2026-02-03T23:12:19","guid":{"rendered":"https:\/\/arvernes-gemmes.com\/?page_id=4582"},"modified":"2026-05-08T17:46:00","modified_gmt":"2026-05-08T17:46:00","slug":"what-is-light","status":"publish","type":"page","link":"https:\/\/arvernes-gemmes.com\/en\/what-is-light\/","title":{"rendered":"The Light"},"content":{"rendered":"<style>.wp-block-kadence-advancedheading.kt-adv-heading4582_3f532a-2f, .wp-block-kadence-advancedheading.kt-adv-heading4582_3f532a-2f[data-kb-block=\"kb-adv-heading4582_3f532a-2f\"]{margin-bottom:var(--global-kb-spacing-sm, 1.5rem);font-size:24px;font-style:normal;}.wp-block-kadence-advancedheading.kt-adv-heading4582_3f532a-2f mark.kt-highlight, .wp-block-kadence-advancedheading.kt-adv-heading4582_3f532a-2f[data-kb-block=\"kb-adv-heading4582_3f532a-2f\"] mark.kt-highlight{font-style:normal;color:#f76a0c;-webkit-box-decoration-break:clone;box-decoration-break:clone;padding-top:0px;padding-right:0px;padding-bottom:0px;padding-left:0px;}.wp-block-kadence-advancedheading.kt-adv-heading4582_3f532a-2f img.kb-inline-image, .wp-block-kadence-advancedheading.kt-adv-heading4582_3f532a-2f[data-kb-block=\"kb-adv-heading4582_3f532a-2f\"] img.kb-inline-image{width:150px;vertical-align:baseline;}<\/style>\n<h1 class=\"kt-adv-heading4582_3f532a-2f wp-block-kadence-advancedheading\" data-kb-block=\"kb-adv-heading4582_3f532a-2f\">What is light?<\/h1>\n\n\n<style>.kadence-column4582_121447-cc > .kt-inside-inner-col,.kadence-column4582_121447-cc > .kt-inside-inner-col:before{border-top-left-radius:0px;border-top-right-radius:0px;border-bottom-right-radius:0px;border-bottom-left-radius:0px;}.kadence-column4582_121447-cc > .kt-inside-inner-col{column-gap:var(--global-kb-gap-sm, 1rem);}.kadence-column4582_121447-cc > .kt-inside-inner-col{flex-direction:column;}.kadence-column4582_121447-cc > .kt-inside-inner-col > .aligncenter{width:100%;}.kadence-column4582_121447-cc > .kt-inside-inner-col:before{opacity:0.3;}.kadence-column4582_121447-cc{position:relative;}@media all and (max-width: 1024px){.kadence-column4582_121447-cc > .kt-inside-inner-col{flex-direction:column;justify-content:center;}}@media all and (max-width: 767px){.kadence-column4582_121447-cc > .kt-inside-inner-col{flex-direction:column;justify-content:center;}}.kadence-column4582_121447-cc {text-align: justify;}<\/style>\n<div class=\"wp-block-kadence-column kadence-column4582_121447-cc\"><div class=\"kt-inside-inner-col\">\n<h2 class=\"wp-block-heading has-text-align-left has-medium-font-size\">Definition <\/h2>\n\n\n<style>.wp-block-kadence-advancedheading.kt-adv-heading4582_6c529b-76, .wp-block-kadence-advancedheading.kt-adv-heading4582_6c529b-76[data-kb-block=\"kb-adv-heading4582_6c529b-76\"]{font-style:normal;}.wp-block-kadence-advancedheading.kt-adv-heading4582_6c529b-76 mark.kt-highlight, .wp-block-kadence-advancedheading.kt-adv-heading4582_6c529b-76[data-kb-block=\"kb-adv-heading4582_6c529b-76\"] mark.kt-highlight{font-style:normal;color:#f76a0c;-webkit-box-decoration-break:clone;box-decoration-break:clone;padding-top:0px;padding-right:0px;padding-bottom:0px;padding-left:0px;}.wp-block-kadence-advancedheading.kt-adv-heading4582_6c529b-76 img.kb-inline-image, .wp-block-kadence-advancedheading.kt-adv-heading4582_6c529b-76[data-kb-block=\"kb-adv-heading4582_6c529b-76\"] img.kb-inline-image{width:150px;vertical-align:baseline;}<\/style>\n<p class=\"kt-adv-heading4582_6c529b-76 wp-block-kadence-advancedheading\" data-kb-block=\"kb-adv-heading4582_6c529b-76\">Light is a form of energy that propagates in the form of waves composed of oscillating electric and magnetic fields. This phenomenon is referred to as \u2018electromagnetic radiation\/waves\u2019 because these two fields are closely linked and interact with each other. These waves, which travel transversely through space, can also be described as a stream of photons, particles that carry this energy.  <\/p>\n<\/div><\/div>\n\n\n<style>.kadence-column4582_68a897-59 > .kt-inside-inner-col,.kadence-column4582_68a897-59 > .kt-inside-inner-col:before{border-top-left-radius:0px;border-top-right-radius:0px;border-bottom-right-radius:0px;border-bottom-left-radius:0px;}.kadence-column4582_68a897-59 > .kt-inside-inner-col{column-gap:var(--global-kb-gap-sm, 1rem);}.kadence-column4582_68a897-59 > .kt-inside-inner-col{flex-direction:column;}.kadence-column4582_68a897-59 > .kt-inside-inner-col > .aligncenter{width:100%;}.kadence-column4582_68a897-59 > .kt-inside-inner-col:before{opacity:0.3;}.kadence-column4582_68a897-59{position:relative;}.kadence-column4582_68a897-59, .kt-inside-inner-col > .kadence-column4582_68a897-59:not(.specificity){margin-top:var(--global-kb-spacing-md, 2rem);margin-bottom:var(--global-kb-spacing-md, 2rem);}@media all and (max-width: 1024px){.kadence-column4582_68a897-59 > .kt-inside-inner-col{flex-direction:column;justify-content:center;}}@media all and (max-width: 767px){.kadence-column4582_68a897-59 > .kt-inside-inner-col{flex-direction:column;justify-content:center;}}<\/style>\n<div class=\"wp-block-kadence-column kadence-column4582_68a897-59\"><div class=\"kt-inside-inner-col\"><style>.wp-block-kadence-image.kb-image4582_dd0fcb-e8:not(.kb-specificity-added):not(.kb-extra-specificity-added){margin-bottom:0px;}.kb-image4582_dd0fcb-e8.kb-image-is-ratio-size, .kb-image4582_dd0fcb-e8 .kb-image-is-ratio-size{max-width:490px;width:100%;}.wp-block-kadence-column > .kt-inside-inner-col > .kb-image4582_dd0fcb-e8.kb-image-is-ratio-size, .wp-block-kadence-column > .kt-inside-inner-col > .kb-image4582_dd0fcb-e8 .kb-image-is-ratio-size{align-self:unset;}.kb-image4582_dd0fcb-e8 figure{max-width:490px;}.kb-image4582_dd0fcb-e8 .image-is-svg, .kb-image4582_dd0fcb-e8 .image-is-svg img{width:100%;}.kb-image4582_dd0fcb-e8:not(.kb-image-is-ratio-size) .kb-img, .kb-image4582_dd0fcb-e8.kb-image-is-ratio-size{padding-bottom:0px;}.kb-image4582_dd0fcb-e8 .kb-image-has-overlay:after{opacity:0.3;}<\/style>\n<div class=\"wp-block-kadence-image kb-image4582_dd0fcb-e8\"><figure class=\"aligncenter size-full\"><a href=\"https:\/\/arvernes-gemmes.com\/wp-content\/uploads\/2026\/02\/Electromagnetic-radiation.gif\" class=\"kb-advanced-image-link\" aria-label=\"Onde \u00e9lectromagn\u00e9tique \u00a9 Et 1mu, CC BY-SA 4.0, via Wikimedia Commons\"><img loading=\"lazy\" decoding=\"async\" width=\"627\" height=\"522\" src=\"https:\/\/arvernes-gemmes.com\/wp-content\/uploads\/2026\/02\/Electromagnetic-radiation.gif\" alt=\"Light is an electromagnetic wave.\" class=\"kb-img wp-image-4366\"\/><\/a><figcaption><em>Animated diagram of an electromagnetic wave \u00a9 Et 1mu, CC BY-SA 4.0, via Wikimedia Commons<\/em><\/figcaption><\/figure><\/div>\n<\/div><\/div>\n\n\n<style>.kadence-column4582_afe594-1e > .kt-inside-inner-col,.kadence-column4582_afe594-1e > .kt-inside-inner-col:before{border-top-left-radius:0px;border-top-right-radius:0px;border-bottom-right-radius:0px;border-bottom-left-radius:0px;}.kadence-column4582_afe594-1e > .kt-inside-inner-col{column-gap:var(--global-kb-gap-sm, 1rem);}.kadence-column4582_afe594-1e > .kt-inside-inner-col{flex-direction:column;}.kadence-column4582_afe594-1e > .kt-inside-inner-col > .aligncenter{width:100%;}.kadence-column4582_afe594-1e > .kt-inside-inner-col:before{opacity:0.3;}.kadence-column4582_afe594-1e{position:relative;}.kadence-column4582_afe594-1e, .kt-inside-inner-col > .kadence-column4582_afe594-1e:not(.specificity){margin-bottom:var(--global-kb-spacing-sm, 1.5rem);}@media all and (max-width: 1024px){.kadence-column4582_afe594-1e > .kt-inside-inner-col{flex-direction:column;justify-content:center;}}@media all and (max-width: 767px){.kadence-column4582_afe594-1e > .kt-inside-inner-col{flex-direction:column;justify-content:center;}}.kadence-column4582_afe594-1e {text-align: justify;}<\/style>\n<div class=\"wp-block-kadence-column kadence-column4582_afe594-1e\"><div class=\"kt-inside-inner-col\"><style>.wp-block-kadence-advancedheading.kt-adv-heading4582_7817a1-fb, .wp-block-kadence-advancedheading.kt-adv-heading4582_7817a1-fb[data-kb-block=\"kb-adv-heading4582_7817a1-fb\"]{padding-bottom:0px;font-style:normal;}.wp-block-kadence-advancedheading.kt-adv-heading4582_7817a1-fb mark.kt-highlight, .wp-block-kadence-advancedheading.kt-adv-heading4582_7817a1-fb[data-kb-block=\"kb-adv-heading4582_7817a1-fb\"] mark.kt-highlight{font-style:normal;color:#f76a0c;-webkit-box-decoration-break:clone;box-decoration-break:clone;padding-top:0px;padding-right:0px;padding-bottom:0px;padding-left:0px;}.wp-block-kadence-advancedheading.kt-adv-heading4582_7817a1-fb img.kb-inline-image, .wp-block-kadence-advancedheading.kt-adv-heading4582_7817a1-fb[data-kb-block=\"kb-adv-heading4582_7817a1-fb\"] img.kb-inline-image{width:150px;vertical-align:baseline;}<\/style>\n<p class=\"kt-adv-heading4582_7817a1-fb wp-block-kadence-advancedheading\" data-kb-block=\"kb-adv-heading4582_7817a1-fb\">Light belongs to the electromagnetic spectrum, which ranges from radio waves to gamma rays. Visible light, on the other hand, corresponds to the part of this spectrum that the human eye is capable of perceiving. It is also called the visible spectrum or optical spectrum, and ranges from wavelengths of approximately 380 to 780 nm.  <\/p>\n\n\n<style>.wp-block-kadence-image.kb-image4582_021e0e-cd:not(.kb-specificity-added):not(.kb-extra-specificity-added){margin-bottom:0px;}.kb-image4582_021e0e-cd.kb-image-is-ratio-size, .kb-image4582_021e0e-cd .kb-image-is-ratio-size{max-width:738px;width:100%;}.wp-block-kadence-column > .kt-inside-inner-col > .kb-image4582_021e0e-cd.kb-image-is-ratio-size, .wp-block-kadence-column > .kt-inside-inner-col > .kb-image4582_021e0e-cd .kb-image-is-ratio-size{align-self:unset;}.kb-image4582_021e0e-cd figure{max-width:738px;}.kb-image4582_021e0e-cd .image-is-svg, .kb-image4582_021e0e-cd .image-is-svg img{width:100%;}.kb-image4582_021e0e-cd:not(.kb-image-is-ratio-size) .kb-img, .kb-image4582_021e0e-cd.kb-image-is-ratio-size{padding-top:0px;padding-bottom:0px;}.kb-image4582_021e0e-cd .kb-image-has-overlay:after{opacity:0.3;}<\/style>\n<div class=\"wp-block-kadence-image kb-image4582_021e0e-cd\"><figure class=\"aligncenter size-full\"><a href=\"https:\/\/arvernes-gemmes.com\/wp-content\/uploads\/2026\/02\/Electromagnetic-spectrum.webp\" class=\"kb-advanced-image-link\" aria-label=\"Spectre \u00e9lectromagn\u00e9tique  \u00a9 Philip Ronan, Gringer, CC BY-SA 3.0, via Wikimedia Commons\"><img loading=\"lazy\" decoding=\"async\" width=\"2000\" height=\"1000\" src=\"https:\/\/arvernes-gemmes.com\/wp-content\/uploads\/2026\/02\/Electromagnetic-spectrum.webp\" alt=\"Electromagnetic spectrum\" class=\"kb-img wp-image-4367\" srcset=\"https:\/\/arvernes-gemmes.com\/wp-content\/uploads\/2026\/02\/Electromagnetic-spectrum.webp 2000w, https:\/\/arvernes-gemmes.com\/wp-content\/uploads\/2026\/02\/Electromagnetic-spectrum-300x150.webp 300w, https:\/\/arvernes-gemmes.com\/wp-content\/uploads\/2026\/02\/Electromagnetic-spectrum-1024x512.webp 1024w, https:\/\/arvernes-gemmes.com\/wp-content\/uploads\/2026\/02\/Electromagnetic-spectrum-768x384.webp 768w, https:\/\/arvernes-gemmes.com\/wp-content\/uploads\/2026\/02\/Electromagnetic-spectrum-1536x768.webp 1536w, https:\/\/arvernes-gemmes.com\/wp-content\/uploads\/2026\/02\/Electromagnetic-spectrum-600x300.webp 600w\" sizes=\"auto, (max-width: 2000px) 100vw, 2000px\" \/><\/a><figcaption><em>Electromagnetic spectrum <br>\u00a9 Philip Ronan, Gringer, CC BY-SA 3.0, via Wikimedia Commons<\/em><\/figcaption><\/figure><\/div>\n<\/div><\/div>\n\n\n<style>.kadence-column4582_d9a0e5-b9 > .kt-inside-inner-col,.kadence-column4582_d9a0e5-b9 > .kt-inside-inner-col:before{border-top-left-radius:0px;border-top-right-radius:0px;border-bottom-right-radius:0px;border-bottom-left-radius:0px;}.kadence-column4582_d9a0e5-b9 > .kt-inside-inner-col{column-gap:var(--global-kb-gap-sm, 1rem);}.kadence-column4582_d9a0e5-b9 > .kt-inside-inner-col{flex-direction:column;}.kadence-column4582_d9a0e5-b9 > .kt-inside-inner-col > .aligncenter{width:100%;}.kadence-column4582_d9a0e5-b9 > .kt-inside-inner-col:before{opacity:0.3;}.kadence-column4582_d9a0e5-b9{position:relative;}.kadence-column4582_d9a0e5-b9, .kt-inside-inner-col > .kadence-column4582_d9a0e5-b9:not(.specificity){margin-top:var(--global-kb-spacing-md, 2rem);margin-bottom:var(--global-kb-spacing-sm, 1.5rem);}@media all and (max-width: 1024px){.kadence-column4582_d9a0e5-b9 > .kt-inside-inner-col{flex-direction:column;justify-content:center;}}@media all and (max-width: 767px){.kadence-column4582_d9a0e5-b9 > .kt-inside-inner-col{flex-direction:column;justify-content:center;}}<\/style>\n<div class=\"wp-block-kadence-column kadence-column4582_d9a0e5-b9\"><div class=\"kt-inside-inner-col\"><style>.wp-block-kadence-advancedheading.kt-adv-heading4582_a17217-9f, .wp-block-kadence-advancedheading.kt-adv-heading4582_a17217-9f[data-kb-block=\"kb-adv-heading4582_a17217-9f\"]{margin-bottom:var(--global-kb-spacing-xxs, 0.5rem);font-style:normal;}.wp-block-kadence-advancedheading.kt-adv-heading4582_a17217-9f mark.kt-highlight, .wp-block-kadence-advancedheading.kt-adv-heading4582_a17217-9f[data-kb-block=\"kb-adv-heading4582_a17217-9f\"] mark.kt-highlight{font-style:normal;color:#f76a0c;-webkit-box-decoration-break:clone;box-decoration-break:clone;padding-top:0px;padding-right:0px;padding-bottom:0px;padding-left:0px;}.wp-block-kadence-advancedheading.kt-adv-heading4582_a17217-9f img.kb-inline-image, .wp-block-kadence-advancedheading.kt-adv-heading4582_a17217-9f[data-kb-block=\"kb-adv-heading4582_a17217-9f\"] img.kb-inline-image{width:150px;vertical-align:baseline;}<\/style>\n<p class=\"kt-adv-heading4582_a17217-9f has--font-size wp-block-kadence-advancedheading\" data-kb-block=\"kb-adv-heading4582_a17217-9f\"><strong>From a fundamental point of view:<\/strong><\/p>\n\n\n<style>.wp-block-kadence-advancedheading.kt-adv-heading4582_3c1c22-da, .wp-block-kadence-advancedheading.kt-adv-heading4582_3c1c22-da[data-kb-block=\"kb-adv-heading4582_3c1c22-da\"]{font-style:normal;}.wp-block-kadence-advancedheading.kt-adv-heading4582_3c1c22-da mark.kt-highlight, .wp-block-kadence-advancedheading.kt-adv-heading4582_3c1c22-da[data-kb-block=\"kb-adv-heading4582_3c1c22-da\"] mark.kt-highlight{font-style:normal;color:#f76a0c;-webkit-box-decoration-break:clone;box-decoration-break:clone;padding-top:0px;padding-right:0px;padding-bottom:0px;padding-left:0px;}.wp-block-kadence-advancedheading.kt-adv-heading4582_3c1c22-da img.kb-inline-image, .wp-block-kadence-advancedheading.kt-adv-heading4582_3c1c22-da[data-kb-block=\"kb-adv-heading4582_3c1c22-da\"] img.kb-inline-image{width:150px;vertical-align:baseline;}<\/style>\n<p class=\"kt-adv-heading4582_3c1c22-da has--font-size wp-block-kadence-advancedheading\" data-kb-block=\"kb-adv-heading4582_3c1c22-da\">\u2013 It propagates in a vacuum at a speed of c=299,792,458 m\/s<br>\u2013 It exhibits wave-particle duality: wave description (frequency, wavelength, polarisation) particle description (photons of energy E=h\u03bd, where E is the energy of the particle in joules, h is Planck\u2019s constant, with an energy of 6.63 \u00d7 10\u207b\u00b3\u2074 J\u00b7s, and \u03bd is the frequency in Hz)<br>\u2013 Its interaction with matter manifests itself through phenomena such as absorption, emission, diffusion, refraction and reflection.<\/p>\n<\/div><\/div>\n\n\n<style>.kadence-column4582_c1ccc3-b0 > .kt-inside-inner-col,.kadence-column4582_c1ccc3-b0 > .kt-inside-inner-col:before{border-top-left-radius:0px;border-top-right-radius:0px;border-bottom-right-radius:0px;border-bottom-left-radius:0px;}.kadence-column4582_c1ccc3-b0 > .kt-inside-inner-col{column-gap:var(--global-kb-gap-sm, 1rem);}.kadence-column4582_c1ccc3-b0 > .kt-inside-inner-col{flex-direction:column;}.kadence-column4582_c1ccc3-b0 > .kt-inside-inner-col > .aligncenter{width:100%;}.kadence-column4582_c1ccc3-b0 > .kt-inside-inner-col:before{opacity:0.3;}.kadence-column4582_c1ccc3-b0{position:relative;}.kadence-column4582_c1ccc3-b0, .kt-inside-inner-col > .kadence-column4582_c1ccc3-b0:not(.specificity){margin-bottom:var(--global-kb-spacing-sm, 1.5rem);}@media all and (max-width: 1024px){.kadence-column4582_c1ccc3-b0 > .kt-inside-inner-col{flex-direction:column;justify-content:center;}}@media all and (max-width: 767px){.kadence-column4582_c1ccc3-b0 > .kt-inside-inner-col{flex-direction:column;justify-content:center;}}.kadence-column4582_c1ccc3-b0 {text-align: justify;}<\/style>\n<div class=\"wp-block-kadence-column kadence-column4582_c1ccc3-b0\"><div class=\"kt-inside-inner-col\">\n<h2 class=\"wp-block-heading has--font-size has-medium-font-size\">Light and gems<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">In gemmology, light is essential for revealing a stone&#8217;s characteristics. A gemstone does not produce its own colour. It owes its colour to the interactions between light and its internal structure. When a ray of light enters a gemstone, several physical phenomena can occur simultaneously:  <\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Reflection:<\/strong> some of the light is reflected back to the surface of the stone, contributing to its brilliance.<\/li>\n\n\n\n<li><strong>Refraction<\/strong>: light changes direction as it enters the gem. This phenomenon depends on the refractive index of each mineral. <\/li>\n\n\n\n<li><strong><a href=\"https:\/\/arvernes-gemmes.com\/en\/what-is-dispersion-in-gemmology\/\" target=\"_blank\" data-type=\"link\" data-id=\"https:\/\/arvernes-gemmes.com\/quest-ce-que-la-dispersion-gemmologie\/\" rel=\"noreferrer noopener\">Dispersion<\/a><\/strong> : certaines longueurs d\u2019onde sont d\u00e9vi\u00e9es plus que d\u2019autres, ce qui d\u00e9compose la lumi\u00e8re blanche en couleurs visibles (effet appel\u00e9 \u00ab feu \u00bb, particuli\u00e8rement marqu\u00e9 dans le diamant).<\/li>\n\n\n\n<li><strong>Selective absorption:<\/strong> certain chemical elements present in the crystal structure absorb specific wavelengths, which determines the colour observed (for example, traces of chromium give rubies their red colour).<\/li>\n\n\n\n<li>Transmission or diffusion: depending on its purity and structure, a stone can allow light to pass through transparently, translucently, or diffuse it.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">The crystal structure also plays an essential role. In certain minerals, light does not propagate in the same way depending on the direction of observation, which can produce pleochroism (color variation depending on the angle). Other gems exhibit particular optical phenomena related to their internal structure, such as iridescence or color play.  <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Thus, the appearance of a gemstone (its color, its <a href=\"https:\/\/arvernes-gemmes.com\/en\/what-is-dispersion-in-gemmology\/\" target=\"_blank\" data-type=\"page\" data-id=\"4422\" rel=\"noreferrer noopener\">dispersion<\/a>, its brilliance, its transparency, etc.) derives directly from the physical laws that govern light and its interaction with matter. Understanding the nature of light therefore makes it possible not only to scientifically explain the beauty of gemstones, but also to interpret the optical phenomena that they present. These properties moreover constitute essential criteria for the identification and study of gemstones.<\/p>\n<\/div><\/div>\n\n\n<style>.kadence-column4582_4d0cca-3f > .kt-inside-inner-col,.kadence-column4582_4d0cca-3f > .kt-inside-inner-col:before{border-top-left-radius:0px;border-top-right-radius:0px;border-bottom-right-radius:0px;border-bottom-left-radius:0px;}.kadence-column4582_4d0cca-3f > .kt-inside-inner-col{column-gap:var(--global-kb-gap-sm, 1rem);}.kadence-column4582_4d0cca-3f > .kt-inside-inner-col{flex-direction:column;}.kadence-column4582_4d0cca-3f > .kt-inside-inner-col > .aligncenter{width:100%;}.kadence-column4582_4d0cca-3f > .kt-inside-inner-col:before{opacity:0.3;}.kadence-column4582_4d0cca-3f{position:relative;}@media all and (max-width: 1024px){.kadence-column4582_4d0cca-3f > .kt-inside-inner-col{flex-direction:column;justify-content:center;}}@media all and (max-width: 767px){.kadence-column4582_4d0cca-3f > .kt-inside-inner-col{flex-direction:column;justify-content:center;}}.kadence-column4582_4d0cca-3f {text-align: justify;}<\/style>\n<div class=\"wp-block-kadence-column kadence-column4582_4d0cca-3f\"><div class=\"kt-inside-inner-col\">\n<h2 class=\"wp-block-heading has--font-size has-medium-font-size\">To summarize<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Light is an electromagnetic wave that travels through a void at a speed of c = 299,792,458 m\/s. It is characterized by a wavelength and a frequency. The portion of light perceptible to the human eye is called the visible spectrum (from 380 nm to 780 nm). In physics, light can also be considered as a flux of photons (energy particles), which illustrates its dual wave-particle nature. It helps explain the visual appearance of gemstones and plays an essential role in their identification.    <\/p>\n<\/div><\/div>\n","protected":false},"excerpt":{"rendered":"<p>What is light? Definition Light is a form of energy that propagates in the form of waves composed of oscillating electric and magnetic fields. This phenomenon is referred to as \u2018electromagnetic radiation\/waves\u2019 because these two fields are closely linked and interact with each other. These waves, which travel transversely through space, can also be described&#8230;<\/p>\n","protected":false},"author":1,"featured_media":4366,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"left","_kad_post_sidebar_id":"sidebar-secondary","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":"","footnotes":""},"wf_page_folders":[226],"class_list":["post-4582","page","type-page","status-publish","has-post-thumbnail","hentry"],"_links":{"self":[{"href":"https:\/\/arvernes-gemmes.com\/en\/wp-json\/wp\/v2\/pages\/4582","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/arvernes-gemmes.com\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/arvernes-gemmes.com\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/arvernes-gemmes.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/arvernes-gemmes.com\/en\/wp-json\/wp\/v2\/comments?post=4582"}],"version-history":[{"count":0,"href":"https:\/\/arvernes-gemmes.com\/en\/wp-json\/wp\/v2\/pages\/4582\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/arvernes-gemmes.com\/en\/wp-json\/wp\/v2\/media\/4366"}],"wp:attachment":[{"href":"https:\/\/arvernes-gemmes.com\/en\/wp-json\/wp\/v2\/media?parent=4582"}],"wp:term":[{"taxonomy":"wf_page_folders","embeddable":true,"href":"https:\/\/arvernes-gemmes.com\/en\/wp-json\/wp\/v2\/wf_page_folders?post=4582"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}