I do not know much about rocks. And the terminology used by the military confuses me. Metals are my thing, in engineering terms.
This link you posted for example, "Rock of over 10,000 psi is considered hard.", the link opens ok but paywall. But hardness is not strength. It's a form of strength, but not the whole picture.
And this in into my ignorance territory, because metals etc for engineering are measured for tensile strength. But rocks are used in compressive tasks. I don't know much on compression of rocks. Done a bit on ceramics though.
I checked how rock harness is measured anyway -
10.62051-ijmee.v7n3.04.pdf
That article is - "Methods and Instruments for Measuring Rock Hardness , Journal of Mech and E Eng". And rock hardness is measured the same as metals. The scales and methods used are Mohs, Shore, Brinell and Vickers. Same as I am familiar with.
That link from "The next big future" opens, and now I am even more confused. Lines like this : "The bomb can penetrate 200 feet of 5000 psi hardened concrete." . I am confused because PSI is not a measure of harness, In concrete ( I had to look it up), PSI is a measure of its compressive strength.
I wish America would get with it by the way, and use METRIC. They should use SI units same as the rest of the world. Ah wait, Trump decided SI means something different now, so that confuses things.
Anyway, hardness and strength are not the same thing. Indeed, hard things tend to be brittle. Glass is hard for example, but brittle.
Also from that article you linked.
"Ultra-high-performance concrete is a new type of concrete that is being developed by agencies concerned with infrastructure protection. UHPC is characterized by being a steel fibre-reinforced cement composite material with compressive strengths in excess of 150 MPa (21750 psi), up to and possibly exceeding 250 MPa (36250 psi). UHPC is also characterized by its constituent material make-up: typically fine-grained sand, silica fume, small steel fibers, and special blends of high-strength Portland cement. Note that there is no large aggregate. The current types in production (Ductal, Taktl, etc.) differ from normal concrete in compression by their strain hardening, followed by sudden brittle failure. Ongoing research into UHPC failure via tensile and shear failure is being conducted by multiple government agencies and universities around the world."
Now I am starting to think I will never understand bunker busting bombs.
Hardness matters for the initial penetration. And granite has a Mohs hardness of 6-7. Quartz will scratch it, so it. As will a steel nail according to a site I looked up. But no mention of if the nail is hardened. Getting more confused now. But what happens after the penetration. See the line above.
" The current types in production (Ductal, Taktl, etc.) differ from normal concrete in compression by their strain hardening, followed by sudden brittle failure."
Yup. Hard things shatter. So these "super concretes" are getting their strength from having included fibers, that are in there to stop crack propagation. And this all leads to toughness.
And toughness is a strange one. That gets into the world of Izod impact testing. Because we can measure and quantify hardness, tensile strength and compressive strength, but toughness is a tough one to quantify. So the IZOD test is used. And the units used for that are Joules per meter squared. It's more of a guide, and really the only way of testing how tough something is to physically smash it.
Sorry for the long ramble. Interesting to look into granite.
Anyway, that is my reasoning that leads me to my conclusion. That the only way to know how effective a bunker buster is, is to test it, against the target, or something very similar.
And this then goes into geology. Some I am not hot on. Because a mountain formation is really a laminate of different rock layers. So even if a bunker buster works well against an Arizona mountain, it might not work against an Iranian mountain.
I am sure Trump has been through all this with his tech people. Or did he sack them all ?