Are elementary particles ultimate fate of black holes?

This is indeed a tempting suggestion (see also this paper). However, there is a crucial difference between elementary particles and macroscopic black holes: the latter are described, to a good approximation, by non-quantum (aka classical) physics, while elementary particles are described by quantum physics. The reason for this is simple.

If the classical radius of an object is larger than its Compton wavelength, then a classical description is sufficient. For black holes whose Schwarzschild radius is bigger than the Planck length this is fulfilled. However, for elementary particles this is not fulfilled (e.g. for an electron the "radius" would refer to the classical electron radius, which is about $10^{-13}$cm, whereas its Compton wavelength is about three orders of magnitude larger).

Near the Planck scale your intuition is probably correct, and there is no fundamental difference between black holes and elementary particles - both could be described by certain string excitations.

The short answer is no. Have a look at the wikipedia article on dissipation of black holes.

quote: Unlike most objects, a black hole's temperature increases as it radiates away mass. The rate of temperature increase is exponential, with the most likely endpoint being the dissolution of the black hole in a violent burst of gamma rays.

The possibility of micro black holes from extra dimensions in some string models still has them dissolving thermodynamically into elementary particles as soon as they are formed.

Edit: Herein I have been replying to the question stated clearly in the last sentence: Is it possible that elementary particles are ultimate nuggets of the final stages of black holes after emitting all the Hawking radiation it could? Not to the different question that people seem to be replying to: "are black holes like elementary particles."

A yes answer to the latter, does not reply to the former, i.e. whether quarks and leptons are the nugget, what is left over, from a black hole. A yes answer to this last would offer the intriguing model of the snake eating its tail, maybe quite probable in some new more encompassing theory, but not foreseen now, at least from the answers given. If after shedding innumerable quarks leptons and photons and entropy on the way, a black hole ends up as an electron (for example) in an identifiable quantum mechanical history.By this last I mean something similar to a decay chain in nuclear cascades.

Yes, black holes are special kinds of elementary particles. That's how they have to be represented in every consistent quantum theory of gravity. This representation of a black hole becomes especially useful and important for small black holes - whose mass is not much larger than the Planck mass.

And indeed, a black hole evaporates, which is just a form of a decay of a heavy elementary particle, and when it becomes very light, at the end of the Hawking evaporation process, it is literally indistinguishable from a heavy elementary particle that ultimately decays into a few stable elementary particles.

However, a difference that you seem to neglect is that black holes actually carry a large entropy $$ S = \frac{A}{4A_0} k_B $$ where $A$ is the area of the black hole's event horizon and $A_0$ is the Planck area $A_0=\hbar G / c^3$. The constant $k_B$ is Boltzmann's constant. This means that there actually exists a huge number of microstates $$ N = \exp(S / k_B ) $$ and a single black hole, with a fixed value of mass, charges, and spin, is just a macroscopic description of the ensemble of $N$ "microstates". In reality, the black hole carries a huge information - the world distinguishes which of the $N$ microstates is actually present.

It is these "microstates" that are really analogous to types of elementary particles. But the number of particle species that macroscopically look like the black hole of given mass, charges, and spin is not one: instead, it is huge, approximately $N$.