Quinqui jargon

Quinqui jargon is associated with "" (tinkers), a semi-nomadic group who live mainly in the northern half of Spain. They prefer to be called "mercheros". They are reduced in number and possibly vanishing as a distinct group.
The language is an old form of Castilian, "Germanía", with elements of Caló, a dialect of the Spanish Roma. The term comes from the word "quincallería" (ironmongery), from ironmongers who originated this cant as part of their trade. Because the men were frequently blamed for petty crime, in modern Spanish the word is associated with references to delinquent, petty thief, or hoodlum. The mercheros identify as a distinct group separate from the Roma "gitanos".
Scholars have many theories about the social origins of "mercheros", summarized as the following: 