Ceramic materials with relatively high resistance to wetting by various liquids, such as water, are presented, along with articles made with these materials, methods for making these articles and materials, and methods for protecting articles using coatings made from these materials. One embodiment is an article comprising a material that is transparent to electromagnetic radiation of at least one type selected from the group consisting of ultraviolet radiation, visible light, and infrared radiation. The material comprises a primary oxide and a secondary oxide. The primary oxide comprises cerium and hafnium. The secondary oxide comprises a secondary oxide cation selected from the group consisting of the rare earth elements, yttrium, and scandium. Another embodiment is an article comprising a material that is transparent to electromagnetic radiation of at least one type selected from the group consisting of ultraviolet radiation, visible light, and infrared radiation. The material comprises a primary oxide and a secondary oxide. The primary oxide comprises cerium or hafnium. The secondary oxide comprises (i) praseodymium or ytterbium, and (ii) another cation selected from the group consisting of the rare earth elements, yttrium, and scandium.