My last shipment of coffee from HasBean also included a Coava Kone filter. The Kone is a filter intended for Chemex coffee makers. There have been rumours about using it for Hario V60 coffee makers, but I don’t know if it will fit as well.
Anyway, the Kone is a stainless steel filter with laser etched holes. The main difference with the usual paper filter is that it lets everything extracted from the coffee pass, without trapping the oils and the flavours.
In a way, the Coava Kone is like the Swissgold filters for the Melitta cone, but the Kone pretty much behaves like the Chemex filter papers. Coffee drips through the filter slightly quicker than through paper, but not as bad as the Swissgold filter.
A downside is that it doesn’t quite catch all the fine particles, leaving a very small amount of sediment in the cup. The sediment is more than paper filter, but not remotely as much as in a press pot.
The Malawi Mzimbi Geisha from HasBean is great for drip brewing, and one of the first I tried in the Kone filter (which btw Steve also sells). This is a shot taken halfway brewing, roughly one minute after the first “blooming” pour. What you see is the last of the second pour dripping through.
A propos, for those not in the know, Malawi is a beautiful southeast African country and a fairly unknown producer of specialty coffee. Gesha (or sometimes Geisha) is a coffee cultivar.
Roughly four minutes after the first pour, the coffee is ready for drinking. Coffee percolates a little faster through the filter compared to Chemex paper, which means the beans must be ground slightly finer. Note that the grounds have not crept up the sides of the filter. The coffee in the filter isn’t like an crater, but almost the reverse; a slight dome shape. This is a result of proper pouring, but also of the way coffee percolates through the Kone filter.
What is interesting to note is that the Kone filter leaves only very little sediment in the cup. It’s a better solution than other permanent filters. More importantly, the Kone filter makes a clearer, more transparent cup than the Chemex paper. In a way the coffee is somewhat like a siphon brew, in which the various tastes and flavours are easier to distinguish.
Despite the cost, I find the Coava Kone filter worth the investment. My only gripe, I wish Coava would also make one for the smaller CM-1 Chemex, the 3-cup brewer that I would normally use most of the time.