Octagon Gemological Services

• Eparchy of Saint Maron of Brooklyn
• Park Slope United Methodist Church
• Waller Temple Church of God in Christ
• Open Door Church of God in Christ
• Historic First Church of God in Christ
• Zion Temple Family Worship Center
• Higher Dimensions Temple of Deliverance
• Church of God of Prophecy
• Iglesia Cristiana Sinaí
• Pride of Baltimore Chorus
• Harbor City Music Company
• St. Clement School