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All 118 elements

Element 89 ·actinide

锕

ā — "actinium"

Actinium

Traditional: 錒

How the character is built

钅

The 钅 radical marks this as a metal, and that is not a coincidence of this one character — it holds right across the table. Read the radical first and the element's state at room temperature is already settled. It is 金 (jīn) squeezed into the space beside another component — radicals change shape by position, which is why 金 is hard to spot until you know to look for 钅.

Phonetic 阿 ā; it names the whole row, 锕系元素, the actinides.

This character is used for the element and little else — you are unlikely to meet it outside a chemistry classroom.

Where it sits among the 118

Actinium melts at 1050°C (1323 K) — lower than 41 of the 97 elements whose melting point has been measured, and higher than 55. The grey dots are the rest of the table.
In the Earth's crust there is present only in traces, far below a milligram per tonne. That makes it commoner than 7 of the 93 elements that occur naturally at all. The scale is logarithmic: each gridline is ten times the one below it.

First isolated in 1899.

The full entry

For stroke order, example sentences, audio and the complete set of meanings, see the dictionary entry.

锕Actinium in the dictionary →

Others built the same way

Every one of these carries 钅, and every one is a metal.

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