What words does Hemingway use to convey to the reader a sense of danger and foreboding considering the physical description of the shark?

From the text:

He was a very big Mako shark built to swim as fast as the fastest fish in the sea and everything about him was beautiful except his jaws. His back was as blue as a sword fish’s and his belly was silver and his hide was smooth and handsome. He was built as a sword fish except for his huge jaws which were tight shut now as he swam fast, just under the surface with his high dorsal fin knifing through the water without wavering. Inside the closed double lip of his jaws all of his eight rows of teeth were slanted inwards. They were not the ordinary pyramid-shaped teeth of most sharks. They were shaped like a man’s fingers when they are crisped like claws . They were nearly as long as the fingers of the old man and they had razor-sharp cutting edges on both sides. This was a fish built to feed on all the fishes in the sea, that were so fast and strong and well armed that they had no other enemy. Now he speeded up as he smelled the fresher scent and his blue dorsal fin cut the water.

When the old man saw him coming he knew that this was a shark that had no fear at all and would do exactly what he wished.