You are actually supposed to leave them more or less like that. RUSTIC is the key word here.
I worked solely for FE for 18 years and did countless metres of those (the black pearlescent retailed at nearly £500, I did a 25mtr. bathroom in those)
All of the showrooms have them done like on the sheets, so that is what the customer is expecting to see, give them anything else and you can't do wrong for doing right.
The client in question had a bath panel done in them by another tiler and was very unhappy with them,
Bbcause of the 'rustic' look. She thought the tiler had done a dreadful job. And the reason for that was that the sample she had was of 12 perfectly aligned and sized pieces on a piece of card, and that's what she wanted. I even went in person to the showroomon the Fulham Road looking for a display, and was told that they didn't sell tiles from Mexico, only from America!!! And they didn't have a display anyway. And even when I showed the assistant their own web page stating that they were hade made Mexican recycled glass tiles she said the website was wrong!
And on the fe website they only show one perfectly aligned sheet.
So I gave the client what she wanted.
I eventually found a small thumbnail image on
glasstile.com (Oceanside) the suppliers website. And it was way too late by then, so I just kept quiet.
And tbh, if done in the 'rustic' style, it's dreadful. Haha