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It also would have reduced competition for a specialty type of cement called slag cement.

The product termed slag cement sets slowly, but ultimately attains a strength scarcely inferior to that of Portland cement.

Other matrices are slag cement, a comparatively recent invention, and some other natural and artificial cements which find occasional advocates.

Slag cement is made by grinding together slaked lime and granulated blast furnace slag.

All concrete used in engineering work is made of either Portland, natural or slag cement, and the great bulk of all concrete is made of Portland cement.