Generating Mesh "Around" 3D Dictionary

I have a 3D Dictionary of points like Dictionary blocks = new Dictionary(); Block is a custom class I made to store data about each point

How would I create a mesh that surrounds all the points but does not create hid faces And how would I texture it so the faces surrounding certain points get certain textures

example in 2d • = a point lines = where I want faces

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 ║• • • ║
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     ║ •║
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I know its not perfect, but its the best I could do with ASSCI