First of all HEX-Craft indeed is the reason for the HEX Folder. It is a XyCraft alike Mod, but with a Dev that isn’t a total transphobe douche that “copyrights” his own unoriginal bad pun of a name.
That is effectively made to look like the IC2 Uranium/Iridium Texture but broken into pieces.
Please dont remind me of my old GT5 Small Ore Texture, it looked so bad. XD
And for Dense Ores, the Textures never came to use, and when I did add Dense Ores they had their dedicated Blocks instead, see the Stone Layers that are Ores, such as Coal, Bauxite, Salt and Quartz.