Yes, the word 'glimmering' is the present participle of the verb
'to glimmer'; the present participle is also an adjective and a
gerund, a verbal noun. Examples:
Verb: The full moon was glimmering on the water of the
swamp.
Adjective: Her glimmering performance brought the audience to
their feet.
Noun: The glimmering is what caught my eye when I found your
ring.