You can just make a plecsi glass by 2 by 2 metters, and on the inside to put senzors that are conected to a battery on the inside of the glass box.These senzors to intersept every cm of the glass,moving,breaking the glass being imposible because all the meccanics are on the inside.And if you want to take the diamont from there like an guard man or somethin' just let everyone know you are takeing it from there and let the alarm to ring.When the senzors are going on they will make a signal to the guard Who are protecting it and come to catch the thief .More details of the placsi glass,first it will be 25 cm thick and scrueld down on the floor.And you can insstal also a gas inside the plecsi glass to put to sleep the Thief and a camera. 1.if the thief has a gas masc you can put a divice like on roice rolls (the brand of car) to retract the diamont in ground and lockit safely. 2.the thief cant cut the wiers or jamm the signal because the mecanism îs on the inside and the signal will be wireless with a wire throw the concre that will go to the guard.The wire having just 10 m and it cant be cut.

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