[1] The band chose their name after the 1958 Yugoslav film Black Pearls, directed by Svetomir Janjić,[1] a story about a reform school teacher's efforts to bring a group of juvenile delinquents to the right path by teaching them diving.

[1] The Serbo-Croatian lyrics for the songs were written by Leposava Stefanović, who would later gain fame as the leader of the dance troupe Lokice.

[4] During the same year, the band also appeared in the Black Wave film When I Am Dead and Gone directed by Živojin Pavlović, portraying a band which accompanies young singers on an audition,[5] and appeared in the TV show Koncert za ludi mladi svet (Concert for Crazy Young People) performing their songs "Ringišpil" ("Carousel") and "Hey Girl", and a cover of the song "Wild Thing".

[1] Dukić had already gained some prominence on the Yugoslav music scene, with his song "San" ("A Dream") competing at Subotica Youth Festival.

[1] The fourth song from the EP, "Nisam više taj" ("I'm not the One Anymore", a cover of "Suddenly You Love Me" by The Tremeloes), was previously recorded with Valčić.

[1] Although the EP received mixed reception by the music critics,[7] the song "Nisam više taj" became a large hit for the band, spending several weeks on the top of the charts in radio shows Minimaks (Minimax) and Sastanak u devet i pet (Meeting at 9:05).

[1] Having released their only full-length studio album, boogie rock-oriented Motorok (Motorock), in 1976, and the single "Ti si uvek htela sve" / "Moj brat i ja" ("You Always Wanted It All" / "My Brother and I"), Dragan Baletić left the band and was replaced by a former Op Cup member Branislav "Cile" Živančević.

[5] After the group split up, for a short period of time Branislav Živančević and his backing band performed under the name Crni Biseri.

[5] With his former Crni Biseri bandmate Jovan Ljubisavljević "Kića" (drums) and former Siluete membet Boban Birtašević (guitar) he formed his Vlada Džet Band.

[5] In 1997, the band reunited with both Dragan Baletić and Branislav Živančević on vocals to hold a concert in the club Crna Maca in Zemun.

[5] During the following year, the compilation album Crni Biseri was released, featuring several previously unreleased songs – "Moja draga" ("My Darling"), "Hey Girl", instrumental track "Mesto pod suncem" ("A Spot under the Sun", a cover of the theme from the 1959 film A Summer Place) and "Kamena vizija" ("Stone Vision", a cover of "Tips of My Fingers" by P. J. Proby), the latter two being their first ever studio recordings, made in 1965.

[5] In 2008, Vladimir Janković published the autobiographical book Godine na 6 (The Years Beginning With 6), about the 1960s rock scene in Belgrade and his work with Crni Biseri.