Identify this Flattened Sea Glass?
by Lyn Johnson
(Seattle, Washington, USA)
 
WHAT IS THIS?! 
 
 
And how would it have been flattened?
 
I am super new to living by the ocean and want to know what these pieces of sea glass could be. 
Some of them have writing or patterns. 
One looks to be a tiny crushed valve/ bottle? 
Any information as to what these could be would be super appreciated! 
Also any tips or tricks to find more/better glass and beaches? 
Or what I should generally look to find? 
I oiled a few of them so the pattern was more visible for the picture, they are all very frosted if that helps.
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