Recently we obtained a beautifully preserved fossil squid with ink still in its ink sac. So we ran a test using ammonia to extract the ink and to see if we could still write with it. The answer is a big yes, and you can see the photographs in our article Fossil Ink Should Make You Think. Download PDF fossil-ink.
Several conclusions are possible:
1) the squid was buried quickly so all body parts are intact;
2) it had to be buried before the ink sac could be fully expelled which is what usually happens when a squid is frightened: and
3) the body had to be preserved without degradation so that the ink sac did not collapse and disintegrate.
Overall this means that overall it was buried quickly, deeply, and in the absence of bugs, air etc. and therefore beautifully preserved.
Of course if you want to believe that the ink has stayed intact for the past hundred plus million years (which modern evolutionist dating would suggest), then all the best to you. The presence of usable ink in the ink sac would suggest this is simply nonsense. And yes we wanted to be original so we went down to the chicken pen this morning and extracted a feather to make the pen with so it had no track record of exposure to any ink compound prior to being use on the squid Fossil.
We are not the first to do this. See our report Writing With Jurassic Ink.
Evidence News 1 December 2011