|3 - 4 cards thick will work if the engraving is being done using a tool that leaves a shallow impression, like the engraving pen.
If the tool being used will leave a deep impression, consider creating the drops using 5 - 6-cards.
When using the colored acrylic slats, the "card" thickness comparison is as follows:
Products sold by Fire Mountain Gems and Beads® are intended for experienced jewelry-makers and designer-artists; children 14 years of age or younger should use these products with adult direction.
Fire Mountain Gems and Beads, Inc. - One Fire Mountain Way, Grants Pass, OR USA 97526-2373
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