Are there any samples big enough to be seen without a microscope? After a decade or more reading about nanotubes and graphene I'm a little jaded about "easily

Are there any samples big enough to be seen without a microscope? After a decade or more reading about nanotubes and graphene I'm a little jaded about "easily manufactured in large quantities". How long does it take to create a solid 1-foot cube? If you are comparing a new material to steel or concrete "large quantities" means multiple tons per hour. I'm going to need to see a sample bigger than a doorstop.