Orville Adelbert Derby, US-born Brazilian geoscientist and geographer (Kelloggsville, Cayuga County, New York State 23 July 1851 – Rio de Janeiro 27 November 1915)

Authored 173 scientific works dealing about geology, mineralogy, palaeontology and archaeology

Gained international recognition for his studies on nepheline rocks associated to phonolite and  foyaite and his petrographical researches 

On nepheline rocks in Brazil. Part I. With special reference to the association of phonolite and foyaite. Quart. J. Geol. Soc. 43:457-75, 1887 

Laid the basis of genetical association between a group of filonian and eruptive rocks

First to study and describe the coexistence of intrusive and extrusive rocks in the same magma (1887)

Proposed the notion of consanguinity of eruptive rocks (1885)

A study in consanguinity of eruptive rocks. J. Geol. 1(6):597-605, 1893

Identified that nepheline rocks were from the same magma with distinct cooling velocities 

Discovered the geologic origin of monazite in gneissic and granitic rock

First to appreciate zircon and monazite as a guide minerals to eruptive rocks

On separation and study of the heavy accessories of rocks. Proceed. Rochester Acad. Sci. 1:198-206, 1891

Peculiar modes of occurrence of gold in Brazil. Am. J. Science 3(28):73-4, 1884

Discovered tinguaite that was named Rosenbusch in 1887

DESCRIBED/NAMED

Queluzite (protore) 1908

Caldasite (1919)

Jacupiranguite (1891)

Marahuite (1907)

METHODOLOGY  

Developed a new method for determination of monazite  

Imagined a process for detaching fossils from limestone matrix employing hydrochloric acid solution

Papers in Science

The genesis of the Diamond. Science 9(207):57-8, 1887

Is The São Francisco do Sul (Santa Catarina) iron a meteorite? Science 20:254-5, 1892

The supposed Tertiary sea of Southern Brazil. Science 13:348-9, 1901

The northeast coast of Brazil in ancient cartography. Science NS 19:681-94, 1904

Review of Branner’s “Stone reefs of Brazil”. Science 21:738-40, 1905

HONORS

Wollaston Medal (1892)

Derbyia Waagen 1884 (Fossil Brachiopoda)

Derbyella Grabau 1931 (Fossil Brachiopoda)

Derbyina Clarke 1931 (Fossil Brachiopoda)

Derbyaeconcha Likharev 1934 (Fossil Brachiopoda)  

Derbyoides Dunbar & Condra 1932 (Fossil Brachiopoda)

Orvillia White 1887 (Fossil Mollusca) 

Derbyella White 1906 (Fossil Plantae)

Derbylite Moore & Araki 1976 (mineral)  

Orvillite Lee 1919 (a zircon variety)