53 Pa. Stat. § 5504
If the instrument under which any real and personal property were or are given, granted, conveyed, bequeathed, devised to, or otherwise vested in, confided to, or awarded to, the city upon charitable use or trust shall authorize or permit the investment of such property or the proceeds thereof in assets of the class other than authorized by law as legal investments, the city may invest and reinvest moneys of the use or trust in any such common trust fund maintained by the city composed of such investments as in the honest exercise of the judgment of the officers of the city charged with the administration of the charitable uses or trusts may, after investigation, be determined to be safe and proper investments; otherwise, such assets shall be invested and reinvested in a common trust fund consisting solely of assets of a class authorized as legal investments for funds held by fiduciaries.
53 P.S. § 5504