Are there any materials, such as a type of tempered glass, that can not be drilled or penetrated by any means (steel drills, diamond drills, saws, lasers, ablation with focused ion beam machines, etc) without some sort of dramatic evidence of such drilling (cracks throughout the entire piece, or a dramatic change of color of an area covering several square centimeters, etc)?
If not, are there materials that can not accept holes over a certain size, but that will accept smaller holes? For instance, maybe there is a material that can accept 50 micron holes but not 1mm holes.
The machinist may or may not have access to a full-fledged laboratory with million-dollar equipment, including things like focused-ion beam machines. If there is a material that resists attacks using inexpensive machines (under $100,000) but not things like focused ion beam machines, that would still be interesting to me.
My goal is to build a tamper-evident container about the size of a brick, perhaps 120mm x 120mm x 180mm. That rules out some materials, such as nitrogen triiodide, which can not be used to make containers.
I'm aware that there are existing ways of building these containers using electronic sensors connected to something, such as a random arrangement of printed wires encased in epoxy, or some sort of mechanical trigger. I seek to develop a more sensitive scheme that is harder to bypass by having the container itself be made out of a material that amplifies the effect of an intrusion attempt.
I'm pretty familiar with tamper-evident seals, and find they all are either pretty easily defeatable (i.e. in a lab setting; perhaps they are good enough for particular field applications), or require detailed non-automated inspection to determine tampering (such as requiring the detailed comparison of before & after photos, as I hear is done using random solder and wire-brush marks on some nuclear program auditing seals). I am also familiar with some micro-level tamper-evident schemes, such as putting an additional patterned metal layer on a chip, with capacitive sensors on the layer below to sense tampering.
I realize these sorts of clever electronic or mechanical schemes can provide some degree of tamper evidence. Lately I've become curious if these traditional approaches can be improved upon by deploying a special material that is inherently tamper evident.