In the examples I found, it looks as if the same capital (whether land or funds) that provided the pin money would fund the widow's jointure when her husband died. The jointure is in a significantly larger amount than pin money, since it serves as the widow's entire income (in lieu of any dower rights in her late husband's estate) instead of an allowance for personal expenses. In the examples, the amount of pin money would be less than the full income of the portion, with the surplus presumably held in trust and to increase the corpus so that the jointure would be fully funded.