The development of the cement industry and technology was a significant driver of progress in construction and artistic applications. Between the late 19th and 20th centuries, cement-based mortars and concrete were widely used in both utilitarian and artistic heritage, serving as structural materials and decorative ornaments. This paper presents a historical overview of the Portuguese cement industry within an international framework. It traces the evolution of modern hydraulic binders from the 18th-century experiments with clay-rich limestone and pozzolan to the 19th-century development of artificial hydraulic lime and major improvements in production processes, kiln design, and chemical analyses, resulting in the standardization of modern artificial Portland cement. These advancements shaped the adaptation and industrialization of cement in Portugal, and marked a gradual transition from natural to artificial cement around the turn of the century. Cement binders imported from England and France continued to dominate the Portuguese market well into the 20th century, even after national production began in the second half of the 19th century. While current research on modern cement heritage often focuses on built structures, this study highlights the cultural significance of cementitious public art. It explores the transition from functional to artistic uses of cement, particularly during the 19th and 20th centuries, through selected case studies that reflect the different techniques and mortar formulations, as well as international influences on Portuguese cementitious heritage. An early example is the Teatro Nacional de São João, where ornaments created with cement-based mortars reinforced with steel bars and metal mesh reflect the influence of French engineering and the pioneering work of Joseph Monier. By contextualizing the Portuguese case within broader technological and artistic trends, this study contributes to a deeper understanding of cementitious heritage and emphasizes the need for further research on Portuguese cement-based artworks from the 20th century. The findings reveal compositional variations and applications that often relied on evolving techniques and experimental mortar formulations. Thus, understanding the material and technical evolution of cement-based mortars, as well as the cross-cultural exchanges that have shaped their use, is essential for the effective preservation and appreciation of this understudied part of modern heritage.