Serum-separating tube Serum-separating tube Serum-separating tubes, also known as serum separator tubes or SSTs, are used in medical clinical chemistry tests requiring blood serum. SSTs are sometimes called "marble-top tubes," "tiger-tops," or "gold-topped tubes", referring to the stoppers which are either gold, red with a gold ring on top, or marbled red and grey. Marble-top tubes are also referred to as "tiger-tops" in some clinics. SPS tubes have a paler colour, sometimes leading confusion; these are known as "yellow tops" not "gold". Trademarked versions include Covidien "Corvac" tubes. They contain a special gel that separates blood cells from serum, as well as
Blood, Sweat & Tears 4 band's cohesion seemed to be disintegrating. Although the album scraped the Top Ten briefly and went gold, it marked the end of BS&T's period of wide commercial success on records." Music critic Robert Christgau's only comments were "Aww-shuck! heck." Additional musicians Album - Billboard (United States) Singles - Billboard (United States) Blood, Sweat & Tears 4 Blood, Sweat & Tears 4 is the fourth album by the band Blood, Sweat & Tears, released in 1971. It peaked at number 10 on the Billboard Pop albums chart. The band invited former member Al Kooper to contribute the song "John the Baptist