A fluid used in a borehole containing suspended solid objects made by an additive manufacturing process. An additive process of solidifying a liquid composition at a succession of selected locations within a workspace, in accordance with a digital design allows a wide variety of shapes to be made. The fluid may be a drilling fluid or a borehole treatment fluid used prior to cementing and the objects may act, possibly in conjunction with other solids, to block loss of fluid into fractures in the formation around the borehole.
