Talk:Engineering brick

Having read both references (after repairing the link rot on the second) there is some ambiguity in that the second suggests that for Engineering Bricks: "...a relatively high proportion of the brick is allowed to melt under reducing conditions (giving a blue-grey brick), so that the pores are sealed by glass..." which may contradict the statement "... engineering bricks (UK Class A) are usually blue due to the higher firing temperature..." from the first reference.

SlySven (talk) 16:51, 15 May 2015 (UTC)