[MeanWestTexan]

"As I understand it, C-14 half life is about 5,700 yrs. It seems that that would make it impossible to date something over 11,400 yrs old using this method."

No. Let's say baseline C-14 is 10,000 parts/million.

5000 parts = 5700 years
2500 parts = 11400 years
1250 parts = 22800
625 parts = 45,500

and so on.

[Old Professer]

So, this old boy was down to his last 1.5 PPM, eh?

[UnbelievingScumOnTheOtherSide]

No. Let's say baseline C-14 is 10,000 parts/million.

5000 parts = 5700 years
2500 parts = 11400 years
1250 parts = 22800
625 parts = 45,500

and so on.

Uh no. First, 10,000ppm (1%) is way too high. We'd be glowing in the daytime. But you also don't double the years.

5000 parts = 5700 years
2500 parts = 11400 years
1250 parts = 17100
625 parts = 22800
312 parts = 28500
156 parts = 34200
78 parts = 39900
39 parts = 45600
19.5 parts = 51300
9.75 parts = 57000
...