How the character is built
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 旦 dàn, retuned to tǎn for the 'ta-' of tantalum.
This character is used for the element and little else — you are unlikely to meet it outside a chemistry classroom.
The element itself
Tantalum was named for a figure condemned to stand in water he could never drink, because the metal sits in acid and refuses to absorb any of it — it is one of the most corrosion-resistant substances known, which is why it is used for implants and for chemical plant that has to handle the nastiest reagents. It also grows an oxide film of exactly controllable thickness, which makes it the basis of the tiny high-capacity capacitors packed into phones and laptops. It occurs with niobium in the ore commonly called coltan, and separating the pair is the hard part.
Where it sits among the 118
First isolated in 1802.
Where it comes from in China
Tantalum is found wherever its chemical twin niobium is found, and telling the two apart is one of the classic hard problems of inorganic chemistry. China's tantalum comes from granite-related sources rather than carbonatite: the lithium-mica granites around Yichun in Jiangxi, where tantalum minerals are recovered alongside the lithium, and, historically, the Koktokay pegmatite in the Altai of Xinjiang, whose great pit was worked out by the end of the last century. The near-inseparability is a quirk of the lanthanide contraction, which leaves the heavier of the pair no larger than the lighter — two different elements with almost the same size and charge.
The full entry
For stroke order, example sentences, audio and the complete set of meanings, see the dictionary entry.
钽Tantalum in the dictionary →Others built the same way
Every one of these carries 钅, and every one is a metal.