U+10443 Deseret Small Letter Eth

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The Deseret alphabet ( ; Deseret: 𐐔𐐯𐑅𐐨𐑉𐐯𐐻 or 𐐔𐐯𐑆𐐲𐑉𐐯𐐻) is a phonemic English-language spelling reform developed between 1847 and 1854 by the board of regents of the University of Deseret under the leadership of Brigham Young, the second president of the Church of Jesus Christ of Latter-day Saints (LDS Church). George D. Watt is reported to have been the most actively involved in the development of the script's novel characters,^: 159 which were used to replace those of Isaac Pitman's English phonotypic alphabet. He was also the "New Alphabet's" first serious user.^: 12 The script gets its name from the word deseret, a hapax legomenon in the Book of Mormon, which is said to mean "honeybee" in the only verse it is used in.

The Deseret alphabet was an outgrowth of the Restorationist idealism and utopianism of Young and the early LDS Church. Young and the Mormon pioneers believed "all aspects of life" were in need of reform for the imminent millennium, and the Deseret alphabet was just one of many ways in which they sought to bring about a complete "transformation in society,"^: 142 in anticipation of the Second Coming of Jesus. Young wrote of the reform that "it would represent every sound used in the construction of any known language; and, in fact, a step and partial return to a pure language which has been promised unto us in the latter days", which meant the pure Adamic language spoken before the Tower of Babel.

In public statements, Young claimed the alphabet would replace the traditional Latin alphabet with an alternative, more phonetically accurate alphabet for the English language. This would offer immigrants an opportunity to learn to read and write English, the orthography of which, he said, is often less phonetically consistent than those of many other languages.^: 65–66 Young also proposed teaching the alphabet in the school system, stating "It will be the means of introducing uniformity in our orthography, and the years that are now required to learn to read and spell can be devoted to other studies."

Between 1854 and 1869, the alphabet was used in scriptural newspaper passages, selected church records, a few diaries, and some correspondence. Occasional street signs and posters used the new letters. In 1860 a $5 gold coin was embossed 𐐐𐐬𐑊𐐨𐑌𐐮𐑅 𐐻𐐭 𐑄 𐐢𐐫𐑉𐐼 (Holiness to the Lord). In 1868–9, after much difficulty creating suitable fonts, four books were printed: two school primers, the full Book of Mormon, and a first portion of it, intended as a third school reader.

Despite repeated and costly promotion by the early LDS Church, the alphabet never enjoyed widespread use, and it has been regarded by historians as a failure. However, in recent years, aided by digital typography, the Deseret alphabet has been revived as a cultural heirloom.

Similar neographies have been attempted, the most well-known of which for English is the Shavian alphabet.