Top roof radical - depicts a peaked roof with a center beam, marking 宝 as something kept inside the home. Same family as 家 home, 安 peace, 守 to guard, 富 wealth. The roof tells you instantly that whatever sits below is sheltered, valued, kept safe.
Bottom 玉 - jade, the supreme imperial treasure. The 1956 simplification kept jade alone as the inner content; traditional 寶 also stacked 缶 pottery and 貝 cowries under the roof. Jade now stands for the whole bundle - a clean compound ideograph of 'treasure under the roof.'
