why cant we fix bangers?

Quartz does not work like boro.  Our torches do not get hot enough, as well as our blowers are not fully skilled in quartz like they are in boro.

how is an opal encased

It is basically vacuumed and sealed in clear glass

You can only encase a synthetic opal and only a gilson synthetic opal.  A natural opal will explode.

How is woodgrain glass made

This is a technique that many blowers use, but only a few have perfected.  It is a mix of laying the colors on and then many times the glass is actually reversed to make the lines go horizontal.