A method of making a free-standing, self-supporting multilayer article comprising: providing a mould defining a first mould cavity, wherein the mould comprises a removable element within the first mould cavity; placing a first particulate component in the first mould cavity; compressing the first particulate component along a first axis in a first compression step to form a first layer of the free-standing, self-supporting multilayer article by applying a first compression force to the first particulate component; removing the removable element from the first mould cavity after formation of the first layer; placing one or more additional particulate components (20, 32) in the mould, wherein a portion of the one or more additional particulate components occupies a space formerly occupied by the removable element; compressing the one or more additional particulate components along the first axis in one or more additional compression steps after removal of the removable element to form one or more additional layers (24, 38) of the free-standing, self-supporting multilayer article, wherein the first layer meets one of the one or more additional layers along a first interface substantially parallel to the first axis and the first layer meets one of the one or more additional layers along a second interface substantially perpendicular to the first axis; and removing the free-standing, self-supporting multilayer article from the mould, wherein the one or more additional compression steps comprise applying a compression force to the one or more additional particulate components prior to removing the free-standing, self-supporting multilayer article from the mould that is greater than the first compression force applied to the first particulate component to form the first layer. providing a mould defining a first mould cavity, wherein the mould comprises a removable element within the first mould cavity; placing a first particulate component in the first mould cavity; compressing the first particulate component along a first axis in a first compression step to form a first layer of the free-standing, self-supporting multilayer article by applying a first compression force to the first particulate component; removing the removable element from the first mould cavity after formation of the first layer; placing one or more additional particulate components (20, 32) in the mould, wherein a portion of the one or more additional particulate components occupies a space formerly occupied by the removable element; compressing the one or more additional particulate components along the first axis in one or more additional compression steps after removal of the removable element to form one or more additional layers (24, 38) of the free-standing, self-supporting multilayer article, wherein the first layer meets one of the one or more additional layers along a first interface substantially parallel to the first axis and the first layer meets one of the one or more additional layers along a second interface substantially perpendicular to the first axis; and removing the free-standing, self-supporting multilayer article from the mould, wherein the one or more additional compression steps comprise applying a compression force to the one or more additional particulate components prior to removing the free-standing, self-supporting multilayer article from the mould that is greater than the first compression force applied to the first particulate component to form the first layer.