美国采购需求：实验室培育裸钻、实验室钻石首饰、实验室培育毛坯钻石、钻石、CVD毛坯钻石、实验室制造钻石

I'm looking to place an order for a custom pendant design, specifically crafted from 18k white gold and set with genuine diamonds. It's essential that the letters and numbers are engraved clearly and durably, ensuring they remain sharp and resistant to fading over time. The pendant should measure 1.0 inches, paired with a 16-inch chain. Could you provide me with the total cost, including all manufacturing, shipping, and any additional fees? I'm also interested in knowing the estimated timeline for production and delivery. Additionally, please share your return or exchange policy in case the final product doesn't meet my expectations. If possible, I'd love to see detailed images of the design and materials beforehand, as well as samples or close-up photos of similar projects you've completed. Looking forward to your response!