File:Guardian Geyser (17 June 2023).jpg

English: Guardian Geyser is located in the southern part of the Porcelain Basin at Yellowstone's Norris Geyser Basin. It is a geyser, but it often behaves as a significant, moderately quiet to moderately noisy fumarole. Water spray is emitted along with white steam. This geyser is frequently misidentified as Black Growler Steam Vent. Its multivent cone consists of relatively smooth to somewhat irregular, whitish to pinkish geyserite that is sometimes covered in places with brownish-green microbial mats. Geyserite terracettes occur on the cone’s runoff channels. A large, prominent vent occurs on the southern side of the geyserite cone - it has relatively thin, upright to overhanging walls and a broadly scalloped to sinuous outline. In June 2023, Guardian Geyser was lightly steaming and occasionally ejecting lazy splashes. Its geyserite cone was much darker-colored than in the past.