Tony Stark: You're from Earth?
Peter Quill: No, I'm from Missouri.
Tony Stark: Yeah, that's on Earth, dipshit.
Peter Quill: I'm gonna ask you this one time, where is Gamora?
Tony Stark: Yeah, I'll do you one better, WHO is Gamora?
Drax: I'll do you one better, WHY is Gamora?
Peter Quill: Dude, don't call us plucky. We don't know what it means. We're more optimistic, yes. I like your plan. Except, it sucks. So let me do the plan and that way it might be really good.
Drax: Tell him about the dance-off to save the Universe.
Tony Stark: What dance-off?
Peter Quill: It's not a thing.
Peter Parker: Like in Footloose, the movie?
Peter Quill: Exactly like Footloose. Is it still the greatest movie in history?
Peter Parker: It never was.
Tony Stark: Don't encourage Flash Gordon.
Peter Quill: Flash Gordon? That's a compliment. Don't forget, I'm half human. So that 50% of me that's stupid that's 100% you.
Peter Quill: How is this dude still alive?
Drax: He's not a dude. You're a dude. This is a MAN. A handsome, muscular man.
Gamora: It's like his muscles are made of Chitauri metal fibers...
Peter Quill: Stop massaging his muscles.
Drax: I've mastered the ability of standing so incredibly still, that I become invisible to the eye. Watch.
Peter Quill: You're eating a Zargnut.
Drax: My movement is so slow that it's imperceptible.
Peter Quill: Mmm, no.
Drax: I'm sure I'm invisible.
Mantis: Hi, Drax.
Drax: Dammit.
Rocket Raccoon: You speak Groot?
Thor: They taught it on Asgard. It was an elective.
Tony Stark: Get lost, Squidward.
Dr. Stephen Strange: I'm Dr Strange.
Peter Parker: Oh, we're using our made-up names? In that case, I am Spider-Man.
Tony Stark: You know Thor?
Peter Quill: Yeah. Tall guy, not that good-looking, needed saving.
Peter Parker: Let me just say, if aliens wind up implanting eggs in my chest or something and I eat one of you, I'm sorry.
Tony Stark: I don't want another single pop culture reference out of you for the rest of the trip. You understand?
Groot: I am Groot.
Steve Rogers: I am Steve Rogers.
Okoye: When you said you were going to open Wakanda to the rest of the world, this is not what I imagined.
T'Challa: What did you imagine?
Okoye: The Olympics, maybe even a Starbucks.
Tony Stark: I swore off dairy, then Ben and Jerry's named a flavor after me.
Dr. Stephen Strange: Stark Raving Hazelnuts.
Tony Stark: It's not bad.
Dr. Stephen Strange: Bit chalky.
Peter Quill: See, "not winging it" isn't really what they do.
Peter Parker: What exactly is it that they do?
Mantis: Kick names, take ass.
Drax: Yeah, that's right.
Bruce Banner: Who's Scott?
Steve Rogers: Ant-Man.
Bruce Banner: There's an Ant-Man and a Spider-Man?
Dr. Stephen Strange: Seriously? You don't have any money?
Wong: Attachment to the material is detachment from the spiritual.
Dr. Stephen Strange: I'll tell the guys at the deli. Maybe they'll make you a metaphysical ham and rye.
Wong: Wait, wait, wait. I think I have two hundred.
Dr. Stephen Strange: Dollars?
Wong: Rupees.
Dr. Stephen Strange: Which is?
Wong: A buck and a half.
Dr. Stephen Strange: What do you want?
Wong: I wouldn't say no to a tuna melt.
Tony Stark: You throw another moon at me and I'm gonna lose it.
Thor: There are six stones out there. Thanos already has the Power Stone because he stole it last week when he decimated Xandar. He stole the Space Stone from me when he destroyed my ship and slaughtered half my people. The Time and Mind Stones are safe on Earth, they're with the Avengers.
Peter Quill: The Avengers?
Thor: The Earth's mightiest heroes.
Mantis: Like Kevin Bacon?
Thor: He may be on the team, I don't know.
Answer: "Doctor Strange" demonstrates that the Infinity Stones are useful in the most dire of situations, when Strange used the Time Stone to prevent Dormammu from taking over the Earth. It's also possible that some of the stones are indestructible. Wanda is able to temporarily destroy the Mind Stone by using her own powers, but the Power Stone will destroy any being that doesn't possess the strength to wield it, and the Reality Stone is shown to have a will of its own and defended itself when it bonded with Jane Foster.
Phaneron ★
Also, in the comics, if the stones are destroyed they will simply be replaced by something else or even stones again. They represent the existence of the universe and cannot be destroyed for real. Always only temporarily.
lionhead