171546
Therefore , different types of iron could be found at different heights inside the furnace , ranging from wrought iron at the top of the tatara ( furthest from the heat , lowest temperature ) , to cast iron towards the middle , and finally steel towards the bottom ( with varying degrees of carbon content . )
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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