Decaying Ball lightning as lightning seems to hit and melt beach sand or silicon crystals.
Around the lightning stroke we observe individual sparks of also individual decaying ball lightning (dark matter according to Q-FFF Theory) falling vertical into the sand and also melting local sand crystals pointing upwards and glued to the main lightning channel of the molten sand structure (Dark matter Hotspot effect) .. see Fulgurite image below.
and: "Fulgurite created by Lightning bullet also known as ball lightning, according to Quantum FFF theory". https://vixra.org/pdf/1805.0307v1.pdf