[9] Mg5(SiO4)2F2 is the end member formula as given by the International Mineralogical Association,[10] molar mass 351.6 g. There is usually some OH in the F sites, however, and Fe and Ti can substitute for Mg, so the formula for the naturally occurring mineral is better written (Mg,Fe,Ti)5(SiO4)2(F,OH,O)2.

[5] The chondrodite structure is based on a slightly distorted hexagonal close packed array of anions O, OH and F with metal ions in the octahedral sites resulting in zigzag chains of M(O,OH,F)6 octahedra.

[2] Chondrodite is biaxial(+), with refractive indices variously reported as nα = 1.592 – 1.643, nβ = 1.602 – 1.655, nγ = 1.619 – 1.675, birefringence = 0.025 – 0.037, and 2V measured as 64° to 90°, calculated: 76° to 78°.

[2] Dispersion: r > v. Chondrodite is found largely in metamorphic contact zones between carbonate rocks and acidic or alkaline intrusions where fluorine has been introduced by metasomatic processes.

It is formed by the hydration of olivine, (Mg,Fe2+)2SiO4, and is stable over a range of temperatures and pressures that include those existing in a portion of the uppermost mantle.