This paper presents a historical perspective of the discovery of, and aspects of, glendonite and ikaite, through the legacy of British mineralogists Douglas Shearman and Alec K. Smith. Much of the knowledge, literature review and synthesis presented in the following paper raises from the original work and discussions that these two key figures in mineralogy shared with the geological community both in the form of their official communications but also as informal discussions with the first author. Through our extensive review, we show that, while the link between ikaite and glendonite is now undeniable, questions remain.