Ravenscroft, George

Ravenscroft, George

▪ English glassmaker
born 1618
died 1681

      English glassmaker, developer of flint glass, a heavy, blown type (shaped by blowing when in a plastic state) characterized by both brilliance and dark shadow.

      Ravenscroft was commissioned by the Worshipful Company of Glass Sellers to experiment with native raw materials for glass manufacture, because the members, dissatisfied with the quality of the glassware available, hoped to make England independent of foreign sources for both raw materials and finished glass.

      In 1674 Ravenscroft obtained a patent for a glass with the desirable quality of a resemblance to rock crystal; this glass was made from a formula including transparent, black flint (a hard mineral of the quartz family), which he called “flint crystalline.” Finding that his pieces tended to lose transparency within several months after manufacture, he added lead, usually in the form of red lead, producing a heavier, denser glass with darker colour and greatly increased refractive power, distinguished by the resonant ring produced when hollow glassware was flicked with the thumb and forefinger. He marked pieces made by the later method with a small glass seal impressed with the raven's head borne on his family coat of arms.

      The new, solid, durable glass gradually achieved a greater market than the more fragile Venetian type, and new techniques, more suitable to the new glass, began to replace methods developed for Venetian glass. Ravenscroft died within a few days after the expiration of his seven-year patent, and other glassmakers immediately began to manufacture flint glass.

* * *

Universalium. 2010.

Игры ⚽ Нужно сделать НИР?

Look at other dictionaries:

  • George Ravenscroft — (1632 7 June 1683) was an English businessman in the import/export and glass making trades. He is primarily known for his work in developing clear lead crystal glass (also known as flint glass) in England.Personal lifeLittle is known about… …   Wikipedia

  • Ravenscroft — is a surname, and may refer to* Edward Ravenscroft, an English dramatist * Edward James Ravenscroft (1816 1890), author of Pinetum Britannicum * George Ravenscroft (1632 1683), developer of lead crystal glass in England * John Ravenscroft *… …   Wikipedia

  • George Baker (actor) — Infobox actor bgcolour = name = George Baker imagesize = caption = birthname = birthdate = birth date and age|1931|04|1 location = Varna, Bulgaria deathdate = deathplace = occupation = Actor spouse = Louie Ramsay (1993 Present) Sally Home (1974… …   Wikipedia

  • John Stark Ravenscroft — (1772 1830) was the first Bishop of the Episcopal Diocese of North Carolina. LifeBorn near Blandford in Prince George County, Virginia in 1772, his early life was spent in Scotland. Ravenscroft did not decide on any profession until he was 27,… …   Wikipedia

  • Thurl Ravenscroft — Infobox actor bgcolour = silver name = Thurl Ravenscroft caption= Ravenscroft s 1970 gospel album Great Hymns in Story and Song imagesize = birthdate = birth date|1914|2|6|mf=y location = Norfolk, Nebraska, U.S. height = deathdate = death date… …   Wikipedia

  • Edward Ravenscroft — (1654? ndash;1707), English dramatist, belonged to an ancient Flintshire family. He was entered at the Middle Temple, but devoted his attention mainly to literature. Among his pieces are * Mamamouchi , or The Citizen turned Gentleman (Dorset… …   Wikipedia

  • Lead glass — Swarovski flacon. Lead glass is a variety of glass in which lead replaces the calcium content of a typical potash glass.[1] Lead glass contains typically 18–40 weight% lead(II) oxide (PbO), while modern lead …   Wikipedia

  • glassware — /glas wair , glahs /, n. articles of glass, esp. drinking glasses. [1705 15; GLASS + WARE1] * * * Introduction       any decorative article made of glass, often designed for everyday use. From very early times glass has been used for various… …   Universalium

  • flint glass — Optics. an optical glass of high dispersion and a relatively high index of refraction, composed of alkalis, lead oxide, and silica, with or without other bases, sometimes used as the diverging lens component of an achromatic lens. [1665 75] * * * …   Universalium

  • industrial glass — Introduction       solid material that is normally lustrous and transparent in appearance and that shows great durability under exposure to the natural elements. These three properties lustre, transparency, and durability make glass a favoured… …   Universalium

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”