Gems as a slot theme covers more ground than the visual similarity might suggest.
The two titles are worth calling out specifically. Pragmatic Play’s Mummy’s Jewels 100 takes gems into Egyptian territory, using jewel and treasure symbols across a high-payline format with the collect mechanic that runs through Pragmatic’s 100-series releases. Gaming Realms’ Slingo Da Vinci Diamonds is the most structurally distinct entry on the page, a Slingo hybrid based on IGT’s original Da Vinci Diamonds slot where the tumbling gem mechanic meets the Slingo number-card format. It plays nothing like the Fortune Gems titles and is worth a demo session if you haven’t encountered the Slingo format before.
The above-average RTP across this page is largely driven by the Fortune Gems entries, which run at 97% across the series. Mummy’s Jewels and Slingo Da Vinci Diamonds operate at different return rates, so it’s worth checking individual game pages if RTP is a factor in how you choose what to play.