That may be used with antecedents Denoting persons, animals or things, and is the proper relative to use when the antecedent includes both persons and things.
"Practical Grammar and Composition"
Thomas Wood
They were having tea on the lawn, a most fascinating tea, with a frosted cake in the middle of the table, on which Pauline's name was inscribed in golden letters, and round which were lighted fourteen little wax candles, Denoting that she had now come to that mature age.
"Girls of the Forest"
L. T. Meade
With a shake of his head, Denoting failure, he made his way to the cottage, unlocked it and entered.
"Only One Love, or Who Was the Heir"
Charles Garvice