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The R 2 O-CaO-MgO-Al 2 O 3 -SiO 2 -Fe 2 O 3 glass ceramics was prepared using granite wastes and Fe 2 O 3 . The effect of Fe 2 O 3 on crystallisation and properties of glass ceramics was studied. Results show that the crystalline phases were Fe 2 TiO 5 and K(NaCa)Mg 5 Si 8 O 22 F 2 when the content of Fe 2 O 3 was low. The main crystalline phase was Fe 1.5 Ti 0.5 O 3 when the content of Fe 2 O 3 was high. With the increase of Fe 2 O 3 , the crystal size of K(NaCa)Mg 5 Si 8 O 22 F 2 reduced and the atomic ratio of Si to Mg increased. The colour of sample varied from greyish green to black with different additions of Fe 2 O 3 . The flexural strength with a maxim (101.02 MPa) when the content of Fe 2 O 3 was 4.7 mol-%. Given the low cost of granite wastes and Fe 2 O 3 , this new type of black glass ceramics is expected to meet the increasing demand from the market of building decoration due to its excellent properties.