The McMillan Lime occurrence is located on the northern half of Lot 3 adjacent to Eagle Bay on the northeast coast of Texada Island.

The deposit is situated within a 13 kilometre long belt of Upper Triassic Vancouver Group, Quatsino Formation limestone up to 13 kilometres wide that is preserved along the axis of a broad northwest plunging syncline. In the vicinity of Eagle Bay three members of the Quatsino limestone outcrop on the eastern limb of an anticline that continues northward to the B.C. Cement quarry (092F 471). The upper magnesian member extends southeast from Grilse Point along the coast past Eagle Bay to Sturt Bay. The underlying middle calcium to high calcium member and the lower high calcium member outcrop as parallel belts flanking the magnesian limestone belt to the southwest. The beds are locally warped into a series of open northwest plunging folds with dips usually not exceeding 40 degrees. Greenstone dykes are present but not as common as at Blubber Bay to the north.

The limestone is generally fine-grained and bluish-grey in colour. Four chip samples taken in succession across 244 metres of calcium to high calcium limestone (middle member) averaged 52.97 per cent CaO, 2.48 per cent MgO, 0.98 per cent insolubles, 0.29 per cent R2O3, 0.24 per cent Fe2O3, 0.033 per cent MnO, 0.016 per cent P2O5, 0.06 per cent sulphur and 43.04 per cent ignition loss (Bulletin 40, page 72). A second set of four chip samples taken southwest of the first set across 244 metres of high calcium limestone (lower member) averaged 55.14 per cent CaO, 0.48 per cent MgO, 0.43 per cent insolubles, 0.16 per cent R2O3, 0.11 per cent Fe2O3, 0.031 per cent MnO, 0.023 per cent P2O5, 0.05 per cent sulphur and 43.55 per cent ignition loss (Bulletin 40, page 72).