The line-up of step-Slice designs carries on using an 11-carat blue spinel and diamond ring along with a fifteen-carat yellow sapphire ring, each from Ceylon, Sri Lanka. Typically often called cobalt blue spinel, stones sourced from Sri Lanka are particularly uncommon and generally darker in colour as a result https://podcasters.spotify.com/pod/show/caratbee/episodes/Circle-of-Eternity-Unveiling-the-Timeless-Allure-of-Round-Engagement-Rings-e2glo7d