Pirastro Oliv Violin String Set - MedManufacture Description The sheep gut core of the Oliv strings is manufactured, wound and polished in the traditional way, by hand. Musicians such as Ilya Gringolts use Oliv strings as they offer the possibility "to explore the remotest corners of sound". The sound is brilliant. Oliv strings offer the typical beautiful sound of gut strings. E String:? Goldsteel string Loop End or Ball End A String:? Aluminum wound over gut core, 13 1 2 gauge D