Thermal Expansion Licence
How is that difficult? My search results aren't personalised either. You could have "made sure" by doing a simple google search but yet again, we see that whizz doesn't think.
or if you don't want to waste a diamond; steel and also alumite are easily obtainable and can mine obsidian (alumite requires obsidian though, so either minium stone or wand of equal trade or IC2 cell recipe will be needed)