A method for producing a large homoepitaxial monocrystalline diamond. The method comprises placing at least two substrates in a substrate holder in a chemical vapor deposition (CVD) chamber. The substrates are positioned in such a manner that the growth faces of the substrates form a wedge. A diamond forming gas is provided adjacent to the substrates in the CVD chamber. The diamond forming gas is exposed to microwave radiation to generate a plasma. Then, the substrates are exposed to the plasma under such conditions that diamond growth occurs in the wedge between the substrates, to form a large homoepitaxial monocrystalline diamond.