i used to live in Uganda and almost all of the cast metal parts for everything there is Chinese (sold by local Indians). I remember buying screws to affix solar panels to my roof and I kept torquing off the heads of the screws. I took a closer look at one of broken ones and it was hollow! I didn't investigate further but I'm pretty the screw was hollow down the entire shank length. since then I've seen pejoratively refer to Chinese steel as chinesium and I'm inclined to agree.