AB Dark Rosin for Violin presented in tied cloth. – Made in England – Unique recipe of Waxes and Timber Resins. 12 per master box. AB Rosin is named after its inventor, Miss Amy Birch. In the latter half of the nineteenth century, Miss Birch perfected a rosin recipe suitable for her own intensive playing schedule. Her achievement, after long experiments, was a compound which worked in harmony with the bow, was unaffected by extremes of temperature or humidity and because of its non-clogging characteristics, helped to produce purity of tone. Professional colleagues at the time persuaded her to make the rosin commercially available, and when it was first launched in 1896, 16 members of the Covent Garden Orchestra endorsed her “AB” rosin in advertisements.