A flapper valve which comprises: a valve body which includes first and second ends (14, 16), a flow bore which extends between the first and second ends, and an enlarged diameter cavity which is formed coaxially within the flow bore; a valve seat which comprises a through bore that is aligned with the flow bore; a retainer which is positioned radially outwardly of the cavity; and a flapper which is pivotally connected to the retainer, the flapper comprising: a sealing side which is configured to engage the valve seat when the flapper is in a closed position; a core which is made of a rigid material; and a resilient coating; characterised in that the flapper further comprises a circular stop ring which is incorporated into the core on the sealing side of the flapper, the stop ring being configured to engage the valve seat when the flapper is in the closed position; and wherein the resilient coating includes at least one of a radially inner portion that is disposed on the core radially inwardly of the stop ring and a radially outer portion that is disposed on the core radially outwardly of the stop ring, the inner and outer portions being configured to sealingly engage the valve seat when the flapper is in the closed position; wherein the stop ring and the radially inner and outer portions (108a, 108b) are configured such that, as the flapper moves into the closed position, the radially inner and outer portions (108a, 108b) will engage the valve seat before the stop ring engages the valve seat; whereby the stop ring limits the extent to which the radially inner and outer portions (108a, 108b) are compressed against the valve seat when the flapper is in the closed position. a valve body which includes first and second ends (14, 16), a flow bore which extends between the first and second ends, and an enlarged diameter cavity which is formed coaxially within the flow bore; a valve seat which comprises a through bore that is aligned with the flow bore; a retainer which is positioned radially outwardly of the cavity; and a flapper which is pivotally connected to the retainer, the flapper comprising: a sealing side which is configured to engage the valve seat when the flapper is in a closed position; a core which is made of a rigid material; and a resilient coating; characterised in that the flapper further comprises a circular stop ring which is incorporated into the core on the sealing side of the flapper, the stop ring being configured to engage the valve seat when the flapper is in the closed position; and wherein the resilient coating includes at least one of a radially inner portion that is disposed on the core radially inwardly of the stop ring and a radially outer portion that is disposed on the core radially outwardly of the stop ring, the inner and outer portions being configured to sealingly engage the valve seat when the flapper is in the closed position; wherein the stop ring and the radially inner and outer portions (108a, 108b) are configured such that, as the flapper moves into the closed position, the radially inner and outer portions (108a, 108b) will engage the valve seat before the stop ring engages the valve seat; whereby the stop ring limits the extent to which the radially inner and outer portions (108a, 108b) are compressed against the valve seat when the flapper is in the closed position. a sealing side which is configured to engage the valve seat when the flapper is in a closed position; a core which is made of a rigid material; and a resilient coating; characterised in that the flapper further comprises a circular stop ring which is incorporated into the core on the sealing side of the flapper, the stop ring being configured to engage the valve seat when the flapper is in the closed position; and wherein the resilient coating includes at least one of a radially inner portion that is disposed on the core radially inwardly of the stop ring and a radially outer portion that is disposed on the core radially outwardly of the stop ring, the inner and outer portions being configured to sealingly engage the valve seat when the flapper is in the closed position; wherein the stop ring and the radially inner and outer portions (108a, 108b) are configured such that, as the flapper moves into the closed position, the radially inner and outer portions (108a, 108b) will engage the valve seat before the stop ring engages the valve seat; whereby the stop ring limits the extent to which the radially inner and outer portions (108a, 108b) are compressed against the valve seat when the flapper is in the closed position.