This is coffee from a coffee bean, commercially ground for a drip-filter coffee machine. Most of the detailed structure that you can see here is due to the grinding process and it does not show you much about the internal structure of the coffee.

Estimate the size of the coffee grounds, and then have a look at the filter paper used to make the coffee. You can also compare this coffee with beans that have been ground for an espresso coffee. It's also very interesting to compare this coffee with instant coffee!