Metallic ink or varnish?

[lofb]

Hello, distinguished group of specialists. For years, I have been using the information found on this forum, and I am grateful for a place where printing specialists can share their experiences.
Thank you very much for that.

I now have a question of my own. I would like to know if the effect shown in the photos below was achieved by printing metallic ink on the film and then applying Cyan/Magenta, or if it was created using some type of varnish (e.g., pearlescent). The substrate is a transparent foil.

All the text on my sample has this effect. Does it mean it comes from a rotogravure?

 

[SteveSuffRIT]

The photo of "effect o letters" is definitely gravure, as noted by serrated edge from screening cells.
You said the substrate is a transparent foil. Did you mean to say transparent film?

 

[lofb]

Yes, I mean transparent film, not opaque foil or anything like that.

Thanks for the clarification about gravure. Does this type of raster point also suggest that it is gravure?

 

[SteveSuffRIT]

All images, even line art (text) is screened in gravure. The exception being Intaglio engraving, which prints currency/money.
The best place to look to identify gravure is at text. The edge will be saw-toothed, ragged, jagged, stairstep'd, rasterized from cell screening.
The photo you show (highlight dots) is difficult to identify the print process.
Not sure what you mean by "raster point"?
Many candy bar wrappers are printed gravure because of their very long run length quantity.

 

[lofb]

All the texts had such ragged edges. I don't deal with gravure usually, rather flexo, so they seemed strange to me.
I am also unable to identify the last sample. These halftone dots are very strange; they have very uneven shapes, and it is difficult for me to determine what printing technique was used.
But thanks for your help Steve, I really appreciate it.
(Raster points - halftone dots?)