Ankerite – [Ca(Fe2+,Mg,Mn2)(CO3)2]

A member of the dolomite group with dolomite and kutnohorite, ankerite is a relatively rare mineral species at Mont Saint-Hilaire.



  • Color is usually pale beige or white.
  • Luster is vitreous to pearly.
  • Diaphaneity is transparent to translucent.
  • Crystal System is hexagonal; R3.
  • Crystal Habits include epitactic growths to 1mm.
  • Cleavage {101} is perfect.
  • Fracture is uneven to subconchoidal.
  • Hardness is 3.5 – 4.
  • Specific Gravity is approximately 2.75 g/cm3.
  • Streak is white.
  • Associated Minerals include albite, chlorite group, elpidite,
    marcasite and sphalerite.
  • Distinguishing Features: Indistinguishable from other members
    of dolomite or calcite groups.
  • Origin: Named in 1825 after Professor Mathias Joseph Anker
    (1771-1843), Austrian mineralogist.



Dana class # – Carbonates; anhydrous carbonates;
dolomite group
Strunz class # V/B.3-20 – Nitrates, carbonates & borates;
water free carbonates [CO3]2- without unfamiliar anions, dolomite group