It was recommended that people used burnt hartshorn, the burnt shells of snails and burnt gypsum.

有人建议人们使用烧过的鹿角、烧过的蜗牛壳和烧过的石膏。

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The difference of effects of burnt lime and hydrated lime, raw gypsum and burnt gypsum on white cement was studied, and the optimal type of lime and gypsum was determined.

研究了生石灰和熟石灰、生石膏和熟石膏对无熟料白水泥的影响差异，确定了最优石灰和石膏类型。

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However, rather than coming from thermite, the metallurgist Professor Sisson thinks the sulphur came from masses of gypsum wallboard that was pulverised and burnt in the fires.

BBC: Q&A: The collapse of Tower 7