Question: What is the date of death of Gustav Von Leonhard's father?

Knowledge 1: Gustav von Leonhard
Gustav von Leonhard (12 November 1816 in Munich – 27 December 1878 in Heidelberg) was a German mineralogist and geologist.He was the son of mineralogist Karl Cäsar von Leonhard.He studied mineralogy and related sciences at the University of Heidelberg, receiving his doctorate in 1840.He continued his education in Berlin, and in 1841 obtained his habilitation at Heidelberg.In 1853 he became an associate professor of mineralogy at the University of Heidelberg.From 1862 until his death, with Hanns Bruno Geinitz, he worked as editor of the Neues Jahrbuch für Mineralogie, Geologie und Paläontologie, a journal founded by his father. [SEP] Knowledge 2: Karl Cäsar von Leonhard
Karl Cäsar von Leonhard (12 September 1779 in Rumpenheim – 23 January 1862 in Heidelberg) was a German mineralogist and geologist.His son, Gustav von Leonhard, was also a mineralogist.From 1797 he studied at the universities of Marburg and Göttingen, where Johann Friedrich Blumenbach was an important influence to his career.He collected many mineralogical specimens on scientific excursions in Saxony and Thuringia, continued by travel to the Austrian Alps (including the Salzkammergut).During his journeys he made the acquaintance of Friedrich Mohs and Karl von Moll.In 1818, through assistance from Baden minister of state Sigismund von Reitzenstein, he was appointed professor of mineralogy at the University of Heidelberg.In 1807 he founded the popular mineralogical journal Taschenbuch für die gesammte Mineralogie — after 1830 the publication was known as Neues Jahrbuch für Mineralogie, Geologie and Paläontologie (edited with Heinrich Georg Bronn).He was a founding member of the "Wetterauischen Gesellschaft" (Wetterau Society).During his career, he maintained correspondence on mineralogical subjects with Leopold von Buch, Johann Wolfgang von Goethe, Abraham Gottlob Werner and Johann Karl Wilhelm Voigt.In 1824 he introduced the term "loess" into the geological science.Nowadays Leonhard is recognized as one of one of the key pioneers of loess studiesThe term "leonhardite" bears his name, being defined as a partially dehydrated, opaque laumontite.
Knowledge 1: Gustav von Leonhard
Gustav von Leonhard (12 November 1816 in Munich – 27 December 1878 in Heidelberg) was a German mineralogist and geologist.He was the son of mineralogist Karl Cäsar von Leonhard.He studied mineralogy and related sciences at the University of Heidelberg, receiving his doctorate in 1840.He continued his education in Berlin, and in 1841 obtained his habilitation at Heidelberg.In 1853 he became an associate professor of mineralogy at the University of Heidelberg.From 1862 until his death, with Hanns Bruno Geinitz, he worked as editor of the Neues Jahrbuch für Mineralogie, Geologie und Paläontologie, a journal founded by his father. [SEP] Knowledge 2: Etan Boritzer
Etan Boritzer( born 1950) is an American writer of children ’s literature who is best known for his book" What is God?" first published in 1989.His best selling" What is?" illustrated children's book series on character education and difficult subjects for children is a popular teaching guide for parents, teachers and child- life professionals.Boritzer gained national critical acclaim after" What is God?" was published in 1989 although the book has caused controversy from religious fundamentalists for its universalist views.The other current books in the" What is?" series includeWhat is Love?,What is Death?,What is Beautiful?,What is Funny?,What is Right?,What is Peace?,What is Money?,What is Dreaming?,What is a Friend?,What is True?,What is a Family?,What is a Feeling?"The series is now also translated into 15 languages.Boritzer was first published in 1963 at the age of 13 when he wrote an essay in his English class at Wade Junior High School in the Bronx, New York on the assassination of John F. Kennedy.His essay was included in a special anthology by New York City public school children compiled and published by the New York City Department of Education.Boritzer now lives in Venice, California and maintains his publishing office there also.He has helped numerous other authors to get published through" How to Get Your Book Published!" programs.Boritzer is also a yoga teacher who teaches regular classes locally and guest- teaches nationally.He is also recognized nationally as an erudite speaker on" The Teachings of the Buddha."
Knowledge 1: Gustav von Leonhard
Gustav von Leonhard (12 November 1816 in Munich – 27 December 1878 in Heidelberg) was a German mineralogist and geologist.He was the son of mineralogist Karl Cäsar von Leonhard.He studied mineralogy and related sciences at the University of Heidelberg, receiving his doctorate in 1840.He continued his education in Berlin, and in 1841 obtained his habilitation at Heidelberg.In 1853 he became an associate professor of mineralogy at the University of Heidelberg.From 1862 until his death, with Hanns Bruno Geinitz, he worked as editor of the Neues Jahrbuch für Mineralogie, Geologie und Paläontologie, a journal founded by his father. [SEP] Knowledge 2: Harry Johnson (wrestler)
Harry Johnson( 1903- date of death unknown) was an English wrestler.

Answer: 23 January 1862