Suraj Radhakrishnan, known as @hobbyist_nanoscope on Instagram, has stunned millions with a viral video that transforms a humble onion peel into a microscopic masterpiece. With over 25 million views, his post titled “Microscopic view of onion fungus and calcium oxalate crystals” reveals a hidden world teeming with life and structure.

To the naked eye, the black dust on the onion skin might seem like harmless grime. But under Suraj’s lens, it’s exposed as a colony of fungal spores, most commonly from the Aspergillus genus. These conidia—tiny reproductive units—belong to fungi in the Ascomycetes or Zygomycetes groups, thriving on moist surfaces and helping the fungus survive in diverse conditions.

But the real visual poetry comes from the calcium oxalate crystals, or raphides, shimmering under polarised light. These needle-like structures are part of the onion’s natural defence system, designed to deter herbivores. Suraj’s use of wet mounts without stains preserves their raw beauty, turning science into art.

we notice a black dust on onions.but when we observe it under microscope,we find that its actually fungal spore(conidia)-most often the fungus Aspergillus species.what looks like simple black dust to the naked eye is in fact living colony of fungi.these spores helps the fungus spread and survive in different conditions.such fungus are usually belongs to the group Ascomycetes or Zygomycetes and thrive on the moist surface of onion.in this microscopy we also reveal beautiful calcium oxalate crystals(raphides) shinning under polarization.the samples we used are wet mounts and no stains used.