What does Collation="A" mean in MySQL Indexes?

Question

In phpMyAdmin I have created a Unique index on a column, in the bottom of the screen I have the following:

Indexes:
Keyname = "[Name of column]"
Type = "BTREE"
Unique = "Yes"
Packed = "No"
Column = "[Name of column]"
Cardinality = "7"
Collation = "A"
Null = ""
Comment = ""

What the heck does collation "A" means? ANSI? ASCII? My column is in utf8_unicode_ci, will it still be guaranteed to be unique even with utf8 characters?

Answer 1

https://dev.mysql.com/doc/refman/5.7/en/show-index.html

How the column is sorted in the index. This can have values A (ascending) or NULL (not sorted).