Note 1: As with all Alternative Texture packs, they only take effect for new placed items (unless you use the Paint Bucket).
Note 2: You can use the Paint Bucket tool from the Alternative Textures framework to change Mini-Obelisks into different colored crystals.
[size=3]Note 3: I highly suggest using my other mod, Multiple Mini-Obelisks to allow for more than 2 Mini-Obelisks.[/size]