What "natural clock"? Starlight? (Your Earth's gravity field vs the rest of the Universe's gravity field argument doesn't work, in fact, I already responded earlier to that argument)
Radioactive decay rates?
101 Evidences for a Young Age of the Earth...And the Universe
http://creation.com/age-of-the-earth
There are none so blind as those who will not read. If all your arguments are so sure and superior then don’t waste your time reading what the strongest opposition has to say - or so you’ve been told - right?!