Ramó Nash is a famous Jamaican artist known for his "Alph-Art."
Captain Haddock ends up purchasing a work of a perspex letter "H" ("Personalph-Art") by Ramó Nash at the Fourcart Gallery. Nash is seen much later as a guest at Endaddine Akass' villa amongst a whole host of other guests who Tintin recognizes from his earlies adventures. Endaddine Akass later revealed to Tintin that he used Nash's "Alph-Art" as a front for large-scale art forgery racket.
Ramó Nash was based on the real-life person Elmyr de Hory. If you look carefully you can see him in Red sea sharks as one of the refugees.
In an interview, Hergé's wife, Fanny Vlamynck stated that Ramó was to save Tintin by tossing Akass off of a railing, as she saw this written in her husband's notes. Is it unknown if the death of the book's villain would be kept or dropped however.
"Alph-Art" is a parody of modern art.