1 Stone countertops, including granite, other natural stone and quartz resin (engineered stone) cost $4-$150 per square foot, or $120-$4,500 for a typical 30 square foot kitchen countertop. 2  Stone tiles cost $4-$20 per square foot; slab stone countertops cost $50-$150 per square foot.
STL (STereoLithography) is a file format native to the stereolithography CAD software created by 3D Systems. STL has several after-the-fact backronyms such as Standard Triangle Language and Standard Tessellation Language.
Virtual Hard Disks (abbreviated to VHDs) are files on the physical machine that store the hard disk contents of a Virtual Machine (VM). Each VHD file is treated as a separate hard disk by WindowsÂ® Virtual PC (WVPC). The Virtual Hard Disk file format is an open standard. For the curious, the specifications of VHD file format can be found here: http://technet.microsoft.com/en-us/virtualserver/bb676673.aspx.