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Blue quartz occurs in a variety of geological settings worldwide and its colour is often produced through the Rayleigh scattering of light off nanometre size mineral inclusions with uncertain identity. Despite this fact, dedicated mineralogical studies on the topic are few and most references mention only the location and inferred causes for the blue colour. The literature consulted for this paper suggests an occurrence pattern consisting mainly of continent-continent collision type zones, with some exceptions owed to local geological particularities. The majority of magmatic, metamorphic and even hydrothermal occurrences are located in zones which underwent upper amphibolitic - granulitic facies conditions and outline the Grenville, Variscan, Pan-African, Ross orogens and others. A link between the causes of the coloration and the geological conditions is also apparent, in the sense that rutile and ilmenite inclusions are most often cited as the colouring agents of magmatic and metamorphic blue quartz, while the hydrothermal variety presumably owes its colour to various mineral or fluid inclusions. The correlation between gold and uranium deposits and blue quartz is also mentioned by various authors. Although a significant number of papers mention the connection between high grade metamorphism and blue quartz at a local or regional scale, the present paper is probably the first to approach the topic at a global scale. The blue quartz occurrence of the Albeşti granite, Argeş County, Romania, an occurrence unknown in the geological literature on blue quartz, is also brought into attention. [ABSTRACT FROM AUTHOR]