Glass and Perspex
There are two qualities of glass. Low quality framing glass has a high iron content which has a green colour to it. It is also cheaper. Low iron glass is much clearer. Perspex is also very clear it is about the same price as low iron glass. Perspex is much lighter in weight.

Mountboard
All mount board is acid free. Museum quality board is more durable. Normal board has a white core which browns over time. Museum board will not brown

  
Backingboard
The two main types of backing board are 3mm MDF and Foamcore. Apparently Foamcore offers more water resisance but I have not noticed any variation in performance between MDF and Foamcore.
Framing Ideas

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