The shelf in the first picture is made of red oak plywood. You can choose the wood type, color and design as you like for your project. In case if you need more help understanding this project, you can refer the source link below. It discusses various items used, steps and tips and personal experience of the author who personally built a Zigzag shelf.
I saw in the March 2019 Vol36,No.1 Iss 259. I have 2 Christian people very close to me that could likely be getting married soon . When I saw the unity cross on page one this would be the perfect gift from a parent. I would like to make it but need the plans. I do not need 3,000 or 60,000 plans I just wish to purchase the plans for the unity cross. I am a beginner so I need detail plans. Please send me information on ordering just the unity cross plans and where to purchase giant Sequoia and white oak woods. Thank you in advance for your help. I need the plans and information before April.