Glass

A glass ball with coloured glass shapes inside
Edo-Kiriko, a traditional cut glass craft in Asakusa, Tokyo, Japan. The glass has two layers, a coloured layer outside a clear layer

Glass is a hard material that can be made in many shapes. It is usually transparent, but it can also be made in colours. Glass is mainly made of silica; glass is made of silica only is called silica glass.

Glass used to make windows and bottles is a specific type called soda-lime glass, composed of about 75% silicon dioxide (SiO2), sodium oxide (Na2O) from sodium carbonate (Na2CO3), calcium oxide, also called lime (CaO), and several minor additives.

By changing the proportions, and adding different ingredients, many kinds of glass can be made. Coloured glass is made by adding small amounts of metal oxides. For example, a blue colour is given by tiny amounts of cobalt oxide.

Crystal glass is made by adding lead and zinc oxides. It is not actually a crystal because all glass is a non-crystalline solid. Crystal glass is called cut glass if it has been cut by hand:

" 'Cut glass' is glass that has been decorated entirely by hand by use of rotating wheels. Cuts are made in an otherwise completely smooth surface of the glass by workers holding and moving the piece against various sized metal or stone wheels".[1]

Because glass is used to make lenses, the word "glasses" means eyeglasses.

The myth that glass is actually a liquid comes from the fact that old windows in houses and churches (200–300 years old) are sometimes a little out of shape: thicker at the bottom than the top. This is actually due to the process of glass making in the past which led to the glass pane being thicker at one edge than the other. It was sensible to install the windows with the thick edge at the bottom. Sometimes a window can be found with the thick edge at the top of the window.

Glass can be recycled over and over. Glass bottles and jars can easily be recycled to make new glass bottles and jars or used in industry as aggregate (building material) or sand.

References

  1. American Cut Glass Association. [1]
Other Languages
Afrikaans: Glas
Alemannisch: Glas
አማርኛ: ብርጭቆ
العربية: زجاج
aragonés: Vidre
ܐܪܡܝܐ: ܙܓܘܓܝܬܐ
asturianu: Vidru
Avañe'ẽ: Itavera
azərbaycanca: Şüşə
تۆرکجه: شوشه
Bân-lâm-gú: Po-lê
башҡортса: Быяла
беларуская: Шкло
беларуская (тарашкевіца)‎: Шкло
български: Стъкло
bosanski: Staklo
brezhoneg: Gwer
буряад: Шэл
català: Vidre
Чӑвашла: Кантăк
čeština: Sklo
Cymraeg: Gwydr
dansk: Glas
Deutsch: Glas
eesti: Klaas
Ελληνικά: Γυαλί
emiliàn e rumagnòl: Vēder
English: Glass
español: Vidrio
Esperanto: Vitro
estremeñu: Vidriu
euskara: Beira
فارسی: شیشه
føroyskt: Glas
français: Verre
Gaeilge: Gloine
galego: Vidro
хальмг: Шил
한국어: 유리
հայերեն: Ապակի
हिन्दी: कांच
hrvatski: Staklo
Ido: Vitro
Bahasa Indonesia: Kaca
interlingua: Vitro
Ирон: Авг
íslenska: Gler
italiano: Vetro
עברית: זכוכית
ಕನ್ನಡ: ಗಾಜು
қазақша: Әйнек
Kiswahili: Kioo
Kreyòl ayisyen: Vè (materyo)
kurdî: Cam
Кыргызча: Айнек
Latina: Vitrum
latviešu: Stikls
lietuvių: Stiklas
Ligure: Veddro
Limburgs: Glaas
lumbaart: Véder
magyar: Üveg
македонски: Стакло
മലയാളം: സ്ഫടികം
Malti: Ħġieġ
मराठी: काच
مصرى: ازاز
Bahasa Melayu: Kaca
မြန်မာဘာသာ: ဖန်
Nāhuatl: Xaltehuilotl
Nederlands: Glas
नेपाल भाषा: खा (वस्तु)
日本語: ガラス
Napulitano: Vrito
нохчийн: Ангали
norsk nynorsk: Glas
occitan: Veire
oʻzbekcha/ўзбекча: Shisha
ਪੰਜਾਬੀ: ਕੱਚ
پنجابی: کنچ
پښتو: ښيښه
Patois: Glaas
polski: Szkło
português: Vidro
română: Sticlă
Runa Simi: Q'ispillu
русиньскый: Скло
русский: Стекло
саха тыла: Өстүөкүлэ
sardu: Bidru
Scots: Gless
sicilianu: Vitru
سنڌي: شيشو
slovenčina: Sklo
slovenščina: Steklo
کوردی: شووشە
српски / srpski: Стакло
srpskohrvatski / српскохрватски: Staklo
Basa Sunda: Kaca
suomi: Lasi
svenska: Glas
தமிழ்: கண்ணாடி
татарча/tatarça: Пыяла
ไทย: แก้ว
Türkçe: Cam
українська: Скло
اردو: شیشہ
ئۇيغۇرچە / Uyghurche: ئەينەك
vèneto: Véro
Tiếng Việt: Thủy tinh
文言: 玻璃
Winaray: Salaming
吴语: 玻璃
ייִדיש: גלאז
粵語: 玻璃
žemaitėška: Stėklos
中文: 玻璃