In some locations in some time periods, estate records may include a "proof of death." This was done to hopefully guarantee that the person whose estate was being settled was actually dead.
Estate records usually allow a genealogist to estimate a death date--typically using the date of the will and the first filing in the case if the estate was testate. In the image shown here, the death date is given in this "Proof of Death" document contained in the probate file. The county where Mimke Habben died was keeping death records at this time, but there is no death certificate on file for him.
The proof of death forms typically says "died on our about" a specific date. Remember the probate court is not as concerned about a precise date of death as genealogists are. The court just wants to make certain the person is dead.
