The use of emoji has received much popular attention in the media and in blogs. There has been less substantive analysis, however, of their linguistic properties though the topic is gathering academic attention. There is as yet no work on how emoji are processed by humans. There is, however, a large body of work on the visual processing of words. My work aims to bring these two areas together to characterise the lexical properties of emoji, using a range of sociolinguistic and psycholinguistic research methods.