allotropy

Before leaving this phase of inorganic chemistry, we may mention other historical examples of allotropy.
Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 1|Various
This would be quite in accordance with the chemical notion of allotropy.
The Making of Species|Douglas Dewar
Allotropy has turned the eyes of many back to the remoter past.
Jewel Mysteries|Max Pemberton
Thus carbon occurs as the diamond, and as charcoal and plumbago, and is therefore regarded as a substance subject to allotropy.
The New Gresham Encyclopedia. Vol. 1 Part 1|Various

The term allotropy (from , of a different nature) was first used by the renowned chemist Berzelius.
The Boy's Playbook of Science|John Henry Pepper

British Dictionary definitions for allotropy

allotropy

allotropism

/ (əˈlɒtrəpɪ) /

noun

the existence of an element in two or more physical forms. The most common elements having this property are carbon, sulphur, and phosphorus

Derived forms of allotropy

allotropic (ˌæləˈtrɒpɪk), adjectiveallotropically, adverb

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