Compressed Redstone is used in the Metallurgic Infuser.
Made in the Enrichment Chamber. Highly recommended as it increases the yield of each redstone tenfold. From 1 redstone dust you obtain 1 compressed redstone. Enriched redstone is 10 times worth in metallurgic infuser compared to redstone dust.
In Mekanism v9, enriched redstone is worth 8 redstone dust in the infuser.