A closer picture would be helpful. It could one of these: http://www.varietyvista.com/02a LC RPMs Vol 1/RPMs 1956D.htm
Info on other collection: American Great Lincoln Collection Penny 1909 = G-4 (?) Penny 1910 = G-4 (?) Penny 1911 = G-4 (?) Penny 1912 = G-4 (?) Penny 1913 = G-4 (?) Penny 1914 = G-4 (?) Penny 1915D = G-4 (?) Penny 1916 = G-4 (?) Penny 1917 = G-4 (?) Penny 1918 = G-4 (?) Penny 1919 = G-4 (?) Penny 1920 = G-4 (?) Penny 1921 = G-4 (?) N0 PLACE HODER FOR 1922(?)*** Penny 1923 = G-4 (?) Penny 1924 = G-4 (?) Penny 1925 – Dbl 1&9 = G-4 (?) Penny 1926 = G-4 (?) Penny 1927 = G-4 (?) Penny 1928 = G-4 (?) Penny 1929 -? (9’s) = G-4 (?) Penny 1930 = G-4 (?) Penny 1931 = G-4 (?) Penny 1932 = G-4 (?) Penny 1933 -? (9-3) = G-4 (?) Penny 1934 = G-4 (?) Penny 1935 – Dbl Die Obverse = G-4 (?) Penny 1936 = G-4 (?) Penny 1937 = G-4 (?) Penny 1938 -Dbl Die Obverse = VG-8(?) Penny 1939 – 9 over 4? = G-4 (?) Penny 1940 = G-4 (?) Penny 1941 = G-4 (?) Penny 1942= G-4 (?) Penny 1943 Steel = AU-50 (?) Penny 1944 = G-4 (?) Penny 1945 = VG-8 (?) Penny 1946 = G-4 (?) Penny 1947 = G-4 (?) Penny 1948S -? (S) = F-12 (?) Penny 1949 = G-4 (?) Penny 1950 = VF-20 (?) Penny 1951D = VF-20 (?) Penny 1952 = VG-8 (?) Penny 1953S = VF-20 (?) Penny 1954S – Closed 9 = VF-20 (?) Penny 1955D = VF-20 (?) Penny 1956D = VF-20 (?) Penny 1957D -? (5) = VF-20 (?) Penny 1958D – Double (D) in GOD = VF-20 (?) Penny 1959D = MS-63RB (?) Penny 1960 -? (R) = MS-63RB (?) Penny 1961D = MS-60RB (?) Penny 1962 - Dbl Die Obverse = MS-60RB (?) Penny 1963D = MS-60RB (?) Penny 1964 = AU-50 (?) Penny 1965 = AU-50 (?) Penny 1966 -? (L) = AU-50 (?) Penny 1967 = AU-50 (?) Penny 1968S = EF-40 (?) Penny 1968S = EF-40 (?) Penny 1969S – Doubled Die Obverse = MS-60 (?) Penny 1970S – Lg Dt (Low 7) = MS-60 (?) Penny 1971S – DblDie Obv = MS-60 (?) Penny 1972D = MS-60 (?) Penny 1973 = MS-60 (?) Penny 1974D = EF-40 (?) Penny 1975D = EF-40 (?) Penny 1976 = EF-40 (?) Penny 1977 = VF-20 (?) Penny 1978D = VF-20 (?) Penny 1979 = AU-50 (?) Penny 1980D = F-12 (?) Penny 1981D = F-12 (?) Penny 1982D -Large Date = F-12 (?) Penny 1983 = VG-8 (?) Penny 1984 = EF-40 (?) Penny 1985 = F-12 (?) Penny 1986D = F-12 (?) Penny 1987D – Small 8 = F-12 (?) Penny 1988 = F-12 (?) Penny 1989D – DblDie Obverse = F-12 (?) Penny 1990 = AU-50 (?) Penny 1991 = AU-50 (?) Penny 1992 = VF-20 (?) Penny 1993D = MS-60 (?) Penny 1994D = AU-50 (?) Penny 1995 = AU-50 (?) Penny 1996 = AU-50 (?) Penny 1997D = AU-50 (?) Penny 1998D = AU-50 (?) Penny 1999D = AU-50 (?) Penny 2000 – DblDie Obverse = MS-60 (?) Penny 2001D = AU-50 (?) Penny 2002 = AU-50 (?) Penny 2003D = AU-50 (?) Penny 2004D = AU-50 (?) Penny 2005D = MS-60 (?) Penny 2006D = MS-60 (?) Penny 2007 = AU-50 (?) Penny 2008D = EF-40 (?) Penny 2009 = AU-50 (?) Penny 2009 -Formative Years Reverse = AU-50 (?) Penny 2009 - Professional Life Reverse = MS-60 (?) Penny 2009 - Presidency Reverse = AU-50 (?) Penny 2010D = AU-50 (?) Penny 2011D = AU-50 (?) Penny 2012 = AU-50 (?) Penny 2013D = AU-50 (?) Penny 2014D = AU-50 (?) Penny 2015D = AU-50 (?) Penny 2016D = AU-50 (?) Penny 2017D = AU-50 (?) Penny 2018D = AU-50 (?)
Info on Here are my set: United States Commemorative Gallery Black Book 1909-1958 Penny 1909 = G-4 (?) Penny 1909 V.D.B. = AU-50 (?) Penny 1910 = AU-50 (?) **** VG-8 Penny 1911 = G-4 (?) Penny 1912 = G-4 (?) Penny 1913 = VG-8 (?)****G-4 Penny 1914 = G-4 (?)****G-4 Penny 1915D – D over D = VF-20 (?)****G-4 Penny 1916D = VG-8 (?) Penny 1917S – (?) = G-4 (?)****Close D Penny 1918 - Brass= G-4 (?)****G-4 Penny 1919S – S over D = VG-8 (?)****D Penny 1920D = G-4 (?) Penny 1921 = G-4 (?) Penny 1922 – Red Brown - Doubled Die Obverse = EF-40 (?) Penny 1923 = G-4 (?) Penny 1924 = VG-8 (?) Penny 1925S - Doubled Die Obverse = F-12 (?) Penny 1926 – Large 6 = F-12 (?) Penny 1927 VDB - Doubled Die Obverse = F-12 (?) Penny 1928D - Doubled Die Obverse = F-12 (?) Penny 1929S = G-4 (?) Penny 1930D = VG- 8 (?) Penny 1931S = AU-50 (?) Penny 1932D – D/D or D/S = F-12 (?) Penny 1933D – Red Brown = MS-60 (?) Penny 1934 = F-12 (?) Penny 1935D = G-4 (?) Penny 1936 – Double Die Obverse = F-12 (?) Penny 1937 = F-12 (?) Penny 1938 = VG-8 (?) Penny 1939S = VG-8 (?) Penny 1940S = VG-8 (?) Penny 1941D – D/D = F-12 (?) Penny 1942D – D/D = VG-8 (?)****(2?) Penny 1943S Steel - Closed R = MS-60 (?)****4 Penny 1944D = AU-50 (?)**** D over S Penny 1945S = F-12 (?)****D/D Penny 1946S – S over D = F-12 (?)****D Over S Penny 1947S- (S) = F-12 (?)****(S) Penny 1948S RB – S over D = VF-20 (?)**** S over D Penny 1949S RB – S over D = VF-20 (?)****D/D Penny 1950D = VF-20 (?) Penny 1951S = VF-20 (?) Penny 1952D = MS63RB (?)****off centered punch Penny 1953D = MS63RB (?)****Dbl Die Penny 1954D – D/D = VF-20 (?) Penny 1955D =VF-20 (?)****Dble Die Penny 1956D - D over D = EF-40 (?) **** Close 9 Dbl D Penny 1957D – Steel = MS-63 (????)****Close 9 Dbl D Penny 1958D – Dbl D = F-12 (?)****Dbl Die Obverse
@NewbietoCoins- I noticed your 14-D slab. You might want to check out this thread. Specifically post 66. I was shocked by the results! https://www.cointalk.com/threads/how-to-remove-scratches-from-slabs.48768/
I have read that! I definitely need to safely, and gently, clean the slab to remove the scratches. I'll work my way through that thread though to make sure I do it properly!
I'd put that one on ebay with a hefty toning premium if it were me. Something along the lines of "a splattering of tan over bright copper red surfaces" BIN $799.99 But seriously, I like the RPM.