In the Cretaceous mud we found a shattered dinosaur thigh by following fragments of petrified bone scattered down an arroyo.
But—I think I’ve explained this before—if you find a tiny piece, how can you tell whether it’s a dissolving dinosaur?
Lick it. If it’s bone, rather than some other stone like agate or silicified wood, the porous vesicles left by once-living cells and capillaries will wick up the moisture of your tongue, and it will stick.
WORLD-BUILDING and WILDERNESS: 
DON’T DO THIS! Archeologists have gotten serious illnesses from licking bone in the field. It also gets human DNA into the bone.
How do you tell, then? In the field, you don’t. You gather up everything that looks like it might be a bone and you bag it. There’s lots and lots of levels of sorting to go through in the lab, and the junk you collect will get thrown out by someone who can tell the difference without licking it.
Hi, Peni–
Thanks, good info for the serious scientist. But I’m just a desert hiker. (We reburied the dissolving dinosaur bone: catch-and-release paleontology.) I’m talking here about chips of–clearly petrified–bone the size of your thumbnail, unlikely to carry any 140,000,000-year-old biota.
And I don’t know what kind of person in an archaeological context would lick bone, but I’m not sure I’d want to know ’em.
I was taught at my Archaeology Field School to lick if in doubt, so most of what I licked was bison bone from 1,000+ years ago. Working in the Archaeology field in the UK recently tho, has changed my mind to the lick-stick test, due to so many burials from the black death. Most American Archaeologists I know weren’t concerned with the fact that the bone they were licking might have been diseased at some point but as soon as I was in the UK… they told me to steer clear!
Hope, that’s so funny–I agree, if I thought something might carry biota that hops to humans–say door handles, used popsicle sticks or other people’s margaritas–I definitely would not lick it. (Heck, I wouldn’t say “good morning” to a T Rex suffering from the Black Death.) The bone we lick isn’t bone any more: all organics have been replaced by stone that preserves the capillary structure, which is what wicks the moisture from the tongue. Licking bone: bad. Licking stone that has replaced bone: safe as houses, though its texture can make your tongue sore.