取两块瓷砖轻轻敲击，如果砖的声音清脆，带着一些金属声则表明其内在的质量非常好，硬度较高；

Take two pieces of tiles tap brick, if the sound is crisp, with some metal sound that its intrinsic quality is very good, the hardness is higher;

youdao

取两块瓷砖轻轻敲击，如果砖的声音清脆，带着一些金属声则表明其内在的质量非常好，硬度较高；

Take two pieces of tiles tap brick, if the sound is crisp, with some metal sound that its intrinsic quality is very good, the hardness is higher;

youdao