C
- Canfieldite: Ag8SnS6 – American mining engineer Frederick Alexander Canfield (1849–1926)
- Cannonite: Bi2(OH)2SO4 – American mineralogist and electron microprobe analyst Benjamin Bartlett (Bart) Cannon
- Carlhintzeite: Ca2AlF7·H2O – German mineralogist Carl Hintze (1851-1916), University of Breslau
- Carlosruizite: K6(Na,K)10Mg10(Se6+O4,SO4,CrO4)12(IO3)12 •12H2O – Chilean geologist Carlos Ruiz Fuller (1916-1997), founder of the Chilean Geological Survey
- Carnallite: KMgCl3•6(H2O) – Prussian mining engineer, Rudolf von Carnall (1804–1874)
- Carnotite: K2(UO2)2(VO4)2 – French mining engineer and chemist Marie Adolphe Carnot (1839–1920)
- Cernyite: Cu2CdSnS4 – Canadian mineralogist Petr Cerny
- Cesbronite: Cu6(TeO3)2(OH) 62H20 – French mineralogist Fabian Cesbron
- Chrisstanleyite: Ag2Pd3Se4 – British mineralogist Christopher John Stanley
- Cleveite: UO2•UO3•PO•ThO2 – Swedish chemist Per Teodor Cleve (1840–1905)
- Clintonite: Ca(Mg,Al)3(Al3Si)O10(OH)2 – American statesman De Witt Clinton (1769–1828)
- Coesite: (form of SiO2) – American chemist Loring Coes, Jr. (1915-1978)
- Coffinite: U(SiO4)1-x(OH)4x – American geologist Reuben Clare Coffin
- Colemanite: (Ca2B6O11•5H2O) – mine owner William T. Coleman (1824–1893)
- Cooperite: (Pt,Pd,Ni)S – South African metallurgist Richard A. Cooper (1890–1972)
- Cordierite: (Mg,Fe)2Al4Si5O18 to (Fe,Mg)2Al4Si5O18 – French geologist Pierre Louis A. Cordier (1777–1861)
- Covellite: CuS – Italian mineralogist Niccolo Covelli (1790–1829)
- Cronstedtite: (Fe2+,Fe3+)3(Si,Fe3+)2O5(OH)4 – Swedish mineralogist Axel Fredrik Cronstedt (1722-1765)
- Crookesite: Cu7(Tl,Ag)Se4 – English chemist and physicist Sir William Crookes (1832–1919)
Read more about this topic: List Of Minerals Named After People