No, the stone we see in S2E20 "Scars" does not appear to be anything from the comics.
--- WARNING: UN-MARKED SPOILERS THROUGHOUT ---
The alien "stone", seen briefly mid-way through the episode, is a complete mystery at the moment. Most of what we know comes from a single brief glance of the artifact and dialogue in the same episode. Here is what we know about it:
While describing her latest vision, Raina alarms Gordon with her description:
RAINA: Last night i saw something beautifully peculiar... it's hard to
describe. It was a giant stone, but not a stone. And then, suddenly,
it was... like an ocean, waves crashing against the shore.
GORDON: Hold on. This stone... were there deep cavities carved into
RAINA: How did you know?
She is next seen discussing the artifact with Jiaying and Gordon:
JIAYING: This could mean the end of us.
RAINA: I don't understand. Have you come across this before?
JIAYING: Only through stories passed down by our ancestors. It's Kree,
dangerous... intended to destroy our people.
RAINA: But didn't they make us?
JIAYING: ... then they decided that we were a mistake. Gordon, do you
think you could locate it? Confirm that it exists?
GORDON: If it's Kree, I suppose I could find a connection to tether.
Later, we get a glimpse of the artifact itself:
Afterwards, the SHIELD personnel discuss the artifact (and why the Inhumans would be after it):
GONZALEZ: We should have destroyed it when we had the chance.
BOBBI: You know we couldn't risk it.
WEAVER: There were too many variables.
MAY: So this is alien.
GONZALEZ: Recovered from a dig site nearly a hundred years ago.
WEAVER: Its energy signatures are unlike anything we've seen before.
This now represents the sum of what we know about the "stone" as fact. That being said, there are a couple of theories that make sense given the direction of the MCU and AoS so far:
The Less Likely Theory
The first theory, but also the less likely of the two, is that the stone is an alien symbiote creature known as a Klyntar. The symbiote is most famously associated with Spider-Man, as his black costume, which was actually an alien symbiote he encountered during the original Secret Wars event.
- Spider-Man is being introduced into the MCU in Captain America: Civil War.
- Several people "in the know", including Kevin Feige himself, have speculated that Spidey might get his black suit in Infinity War 1 or 2.
- The "stone" is unlike anything SHIELD has seen before, yet they have encountered Kree technology & biology before. The stone may have been brought to Earth by the Kree but is not actually Kree in origin.
- The "stone" appeared to be changing shape on its own, perhaps even by will.
- In its liquid/transforming state, the "stone" appears nearly identical to the symbiote creatures (a black oily substance).
- The symbiotes are violent, near-unstoppable creatures whose only weakness is sound. They could, in theory, make a formidable weapon against Inhumans.
The More Likely Theory
The second, and more likely theory, is that the "stone" is actually the source of the Diviners seen already throughout Season 2 of AoS.
- The artifact is said to be Kree in origin.
- The "stone" in its solid form appears to be made of the same material as the Diviners.
- The liquefying effect of the stone is very similar to the effect it has on humans who touch the Diviners, turning them into some sort of black, stony ash-like material.
- The "stone" contains several square-shaped holes, and the Diviners look like a square peg that was then twisted vertically.
- When held by a latent Inhuman, a Diviner's surface "morphs" to show Kree writing. The effect is very similar to the liquid-like transformation of the "stone" when we see it.
- If the "stone" is indeed the source of the Diviners, it could conceivably be a weapon against the Inhumans by un-doing the terrigenesis performed by the Diviners. This would essentially render all Inhumans human again, thereby "destroying" them as a people.
As it stands, we will simply have to wait for future episodes and hope that more information about the "stone" is revealed. However, given that it appears to be central to the upcoming conflict between SHIELD and the Inhumans, it's fairly certain that haven't seen the last of this artifact.
UPDATE: At the end of the season finale "S.O.S.", Simmons is working near the stone and finds the door unlatched. As she goes to re-seal it,
the stone seemingly comes alive and leaps out of the case, absorbing a screaming Simmons into it before returning to normal.
This scene would seem to lend heavy evidence towards the first theory, with the stone being a living entity of some kind.
UPDATE 2: As of Season 3, we now know that the stone is a Kree device that can open portals to other worlds when certain vibrational frequencies are directed at it. An ancient faction of Hydra has been in possession of the stone for centuries while attempting to release an Inhuman trapped on a desolate world.