Rarest Actinide — All 15 Answers Ranked by Rarity
15 answers are accepted for “Name an actinide”. Mendelevium is the rarest actinide in this ranking, with 42,374 monthly Wikipedia views (rarity 1.000, Legendary). Nobelium is the second-rarest with 45,183 monthly Wikipedia views, 1.07× the figure for Mendelevium. Uranium is the most common actinide in this ranking, with 472,229 monthly Wikipedia views, 11.1× the figure for the rarest. Combined monthly Wikipedia views across the 15 answers: 2,003,583. Mendelevium is 2.1% of that total. 3 answers are Epic or Legendary: Mendelevium (Legendary), Nobelium (Epic), and Fermium (Epic).
Quick answer
Monthly English Wikipedia pageviews. Source: Wikidata + Wikipedia pageviews (2026-10).
Ranked answers
| Rank | Answer | Tier | Rarity | Monthly Wikipedia views |
|---|---|---|---|---|
| 1 | Mendelevium on Wikipedia | Legendary | 1.000 | 42,374 |
| 2 | Nobelium on Wikipedia | Epic | 0.929 | 45,183 |
| 3 | Fermium on Wikipedia | Epic | 0.857 | 53,341 |
| 4 | Berkelium on Wikipedia | Rare | 0.786 | 56,486 |
| 5 | Lawrencium on Wikipedia | Rare | 0.714 | 63,975 |
| 6 | Actinium on Wikipedia | Rare | 0.643 | 81,378 |
| 7 | Curium on Wikipedia | Uncommon | 0.571 | 84,648 |
| 8 | Neptunium on Wikipedia | Uncommon | 0.500 | 87,863 |
| 9 | Einsteinium on Wikipedia | Uncommon | 0.429 | 96,535 |
| 10 | Americium on Wikipedia | Familiar | 0.357 | 110,319 |
| 11 | Californium on Wikipedia | Familiar | 0.286 | 123,052 |
| 12 | Protactinium on Wikipedia | Familiar | 0.214 | 173,138 |
| 13 | Thorium on Wikipedia | Common | 0.143 | 194,212 |
| 14 | Plutonium on Wikipedia | Common | 0.071 | 318,850 |
| 15 | Uranium on Wikipedia | Common | 0.000 | 472,229 |
FAQ
What is the rarest actinide?
Mendelevium is the rarest actinide in this ranking, with 42,374 monthly Wikipedia views (rarity 1.000, Legendary).
How many actinides are there?
There are 15 actinides in this ranking, from Mendelevium (rarest) to Uranium (most common).
What is the most common actinide?
Uranium is the most common actinide in this ranking, with 472,229 monthly Wikipedia views (Common).
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Sources
Recorded source: Wikidata + Wikipedia pageviews (2026-10). The answer list is compiled from Wikidata (CC0), and the view counts are monthly English Wikipedia pageviews. Rarity is the percentile of the popularity figure inside this prompt: 1 is the rarest and 0 is the most common. Linked names open the English Wikipedia article stored on that answer.