Of the "Japanese vaults" that I have seen, that are REAL, they are not really vaults like something you walk into. This is a specially mixed cement that can be used for a number or reasons. I have seen it used as a capping layer, flat boundary, as a cap or hat shaped shield and as a box shape encasing the treasure. If it is for boxing or such and most often as a cap and shield, it will measure in even Meter increments. The color is a very light tan or off white with the slightest of yellow cast to it. The crystal structure is very fine or creamy, there is no aggriget or inclusions. The surface will be smooth as if it was trowled smooth, which it often is. Sharp corners to the shape. And it is really HARD. Concrete or cement is easier to break because for among other reasons, the mix of shapes and larger grain size of the mix, makes for easier fracturing or breaking. The more homogeneous a mix is, the harder it is to break down or cut. This is not a traditional lime stone cement. It is a special mix of naturally occurring material found only in China.
The last REAL vault box's I personally examined, that is stood on, ran my hands on and whacked on with a hammer, was two years ago. One was 1meter x 2meter and the other was 3meter x 3meter. Both were next to each other. The smaller one was found at the base of a set of stairs and the larger one is dead square in the middle of the room. This was just 12 inches under the floor of the inside of an old Filipino government building. Not possible to open them as the PH government did not want them to be opened. So I guess some senator, governor or president will do that themselves after I identified and located them, for them naturally. Oh well I tried.
