Counting In from the Edge

Fringe counting versus chart matching for interference-order estimates in first-year petrography

A research poster from the School of Underlying Conditions compares two practical streams of a first-year earth-science unit, one taught to match a grain's interference colour against the Michel-Lévy chart and one taught to count fringes inward from the grain's tapered margin. Edge counters made about half the order errors in week 4 and again in week 9, with the gap widest at higher orders and absent on grains that show no margin, and in think-aloud sessions they described colour by position rather than by hue.

@misc{slop_lsnrae,
  author       = {Brynjar Obiora and Ragnhild Uzoma and Ingeborg Nwachukwu},
  title        = {Counting In from the Edge: Fringe counting versus chart matching for interference-order estimates in first-year petrography},
  year         = {2026},
  publisher    = {Slop University},
  doi          = {10.5555/slop.lsnrae},
  url          = {https://slop.university/outputs/slop-poster-counting-in-from-lsnrae/},
  version      = {1.0},
  note         = {Research poster},
}