Composition of cortical bone
Tissue Biomechanics Class   Biomechanics articles bone.
Rod Lakes, University of Wisconsin

Mineral, mostly hydroxyapatite Ca10(PO4)6(OH)2 .
Organic, mostly collagen protein
Polysaccharides and related

percent by weight
less than 1
  After Tiffit (1980) The organic matrix of bone tissue. In Fundamental and Clinical Bone Physiology, chapter 3. Ed. M. R. Urist. J. B. Lippincott, Philadelphia.

  As for porosity in cortical bone, canaliculi account for 1.5 percent of the volume and osteocyte lacunae comprise 0.8 percent of the volume according to Frost, H., "Measurements of osteocytes per volume and volume components of osteocytes and canaliculi in man", Henry Ford Hospital Medical Bulletin, 8, 208-211, (1960).

  The Haversian canals account for about 4.5 - 6 percent of the volume of human compact bone based on cross section area measurements. Fibular bone has larger osteons than femoral bone. See, for example, Evans, F. G. and Bang, S., Physical and histological differences between human fibular and femoral compact bone. Studies on the anatomy and function of bones and joints, edited by Evans, F. G., 145-155, Springer, (1966).