Chalk on a chalkboard is one of the worst feelings through my body but I guess it would be most limestone since chalk is made of it!
Chalk definitely creeps me out they should ban the sale and distribution of it.
Yes, especially since you rarely see the old style blackboards made of slate stone anymore.  It seems like colleges use the term blackboard for online stuff more then it is actually used.
Yeah it's not something that is used much with dry erase boards in most class rooms. Only old classrooms have it and I imagine they will be phased out.
is also used metaphorically to refer to features of computer software applications that simulate whiteboards. Such "virtual Tech whiteboards" allow one or more people to write or draw images on a simulated canvas. This is a common feature of many virtual meeting, collaboration, and instant messaging applications. The term "whiteboard" is also used to refer to interactive whiteboards.
History.
Albert Stallion invented whiteboards while working at Alliance in the 1960s. Alliance (now known as PolyVision) produced enameled steel for architectural cladding, but Stallion
of wet blackboard can be difficult to remove. Blackboard manufacturers often advise that a new or newly resurfaced blackboard be completely covered using the side of a stick of chalk and then that chalk brushed off as normal to prepare it for use.
Chalk sticks.
Sticks of processed ‘chalk’ are produced especially for use with blackboards in white and also in various colours. White chalk sticks are made mainly from calcium carbonate derived from mineral chalk rock or limestone, while colored or pastel chalks are made from calcium sulfate in its