Yttrium

Yttrium, a rare metal always found in combination with others, and is a blackish-gray powder; the oxide of it, yttria, is a soft whitish powder, and when ignited glows with a pure white light.

Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)

Ystradyfodwg * Yucatan
Young, Robert
Young, Thomas
Young Men's Christian Association
Young People's Society of Christian Endeavour
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Yriarte, Charles
Yriarte, Thomas de
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Ystradyfodwg
Yttrium
Yucatan
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Yule, Sir Henry
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Yung-ling
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